Microbiology with Diseases by Taxonomy Chapter 24 Answers

Microbiology with Diseases by Taxonomy Answers

Microbiology with Diseases by Taxonomy Chapter 24 Answers 1CM
The herpes viruses are belongs, to the family Herpesvirdae. Many viruses belongs to this family are infective to the humans. Among them are herpes simplex, varicella-zoster, and Epstein-Barr viruses are infecting 90% of the adults in US. The concept map of herpes simplex virus is as follows.
microbiology-with-diseases-by-taxonomy-chapter-24-answers-1cm

Microbiology with Diseases by Taxonomy Chapter 24 Answers 1CT
The replication of poxvirus occurs in the cytoplasm of the infected cell. This is a unique feature. The problem is that the cytoplasm does not contain DNA. The DNA is present only in the nucleus of the host cell.
In the case of poxvirus, DNA replication takes place in virosomes. Virosomes are the regions in the cytoplasm of the infected cell, and it does not have any cellular organelles. These virosomes are foci of DNA replication and morphogenesis of poxvirus.
Then secondary uncoating takes place and viral genomes are released into the cytoplasm of the infected cell. This process brings the DNA template and replication proteins, which are newly synthesized into contact.
As the poxvirus is large, replication is quick, and takes almost 12 hours. Then the infected cell dies due to the release of viruses.
For genome transcription, poxvirus encodes its own machinery. The machinery includes DNA dependent RNA polymerase and other activating, modulating proteins extra. Hence, replication in cytoplasm is possible for poxvirus.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 1L
The stages of lesion in poxvirus infection:

The poxviruses produce lesions in a series of stages.
The lesions are flat and red. This is macular stage.
The lesions are raised sores. This is popular stage.
The lesions are filled with clear liquid. This is vesicular stage.
The clear fluid changes into pus and is called pustular stage.
Pustules dry up and form crust.
As the dermis is penetrated by the lesions scar is formed.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 1M

The disease, chicken fox is caused by the virus, varicella- zoster. This virus belongs to the family Herpesviridae. This disease is transmitted, through the air hence; it is called air borne disease. Thus, the matching answer is (B) Herpesviridae.
The disease, Smallpox is caused by variola virus. This virus is belongs to the family Poxviridae. The variola virus is existed in two forms; they are variola major and variola minor. It is a very infectious disease affects the skin, blood vessels and respiratory mucosa extra. Thus, the correct matching answer is (A) Poxviridae.
The disease, Cowpox is caused by poxvirus. This virus is belongs to the family Poxviridae. The cows are affected by this disease; sometimes, this may leads to death of cow. Thus, the correct matching answer is (A) Poxviridae.
The disease, Molluscum contageosum is caused by Molluscipoxvirus. This virus belongs to the family Poxviridae. It is a human specific pox disease, often associated with acquired immuno deficiency syndrome (AIDS). Thus, the correct matching answer is (A) Poxviridae.
The disease, Human herpesvirus 1 (HHV-1) infection is caused by Human herpesvirus 1 (HHV-1) virus. This virus belongs to the Herpesvirdae family. This disease, is also called oral herpes, it mainly affects the lips and forms itchy skin lesions. Thus, the correct matching answer is (B) Herpesvirdae.
The disease, Whitlow is caused by HHV-1 or HHV-2 virus. This virus belongs to the family Herpesviridae. Thus the correct matching is (B) Herpesviridae.
The disease, Shingles is caused by varicella-zoster virus. It belongs, to the family Herpesviridae. Thus the correct matching is (B) Herpesviridae.
The disease, Burkett’s lymphoma is caused by Epstein – Barr virus. It is belongs, to the Herpesviridae family. Thus the correct matching is (B) Herpesviridae.
The Infectious mononucleus is caused by Epstein – Barr virus. It is belongs, to the family Herpesviridae. Thus the correct matching is (B) Herpesviridae.
The disease, chronic fatigue syndrome is caused by Epstein – Barr virus. It is belongs, to the family Herpesviridae. Thus the correct matching is (B) Herpesviridae.
The disease, Cytomegalovirus infection is caused by Cytomegalovirus. It is belongs, to the family Herpesviridae. Thus the correct matching is (B) Herpesviridae.
The disease, Genital warts is caused by papillomavirus. It is belongs, to the family Papillomaviridae. Thus, the correct answer is (C) Papillomaviridae.
The disease, Roseola is caused by Human herpesviurs-6. It belongs, to the family Herpesviridae. Thus the correct matching is (C) Herpesviridae.
The disease, plantar warts is caused by papillomavirus. It is belongs, to the family Papillomaviridae. Thus, the correct answer is (C) Papillomaviridae.
The disease, Progressive multifocal leukoencephalopathy is caused by latent infections of JC virus it belongs, to the family Polymaviridae. Thus, the correct matching is (G) Polymaviridae.
The disease, Common cold is caused by adenovirus. It is belongs, to the family Adenoviridae. Thus, the correct answer is (D) Adenoviridae.
The disease, Hepatitis B is caused by Hepatitis B virus. It is belongs, to the family Hepadnaviridae. Thus, the correct matching is (E) Hepadnaviridae.
The disease, Fifth disease is caused by B19 virus. It belongs, to the family Parvoviridae family. Thus, the correct matching is (F) Parvoviridae.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 1MC
DNA (deoxyribonucleic acid) virus in Poxviridae is relatively large and well suited potentially for vaccinations and introduction of genetic material in gene therapy. This virion is very large. It is of the size of 200 nm in diameter and 300 nm in length. The shape is usually like a rounded brick wrapped around by endoplasmic reticulum (ER). The entire genome is a linear, double stranded DNA segment.

The vaccinia virus of this family is the active agent in the small pox eradication. Also, it is used effectively for foreign protein expression. It shows a strong host immune response. Hence, the correct option (b).
Herpesviridae is a large family of DNA viruses. The viruses which belong to this family are called herpesviruses. Some of these viruses like Varicella Zoster virus, Epstein – Barr virus, cytomegalovirus, HSV-1, and HSV-2 are widespread among humans. Herpes viruses are large double stranded linear DNA genomes. They are not suited for vaccinations and gene therapy. Hence, the option (a) is not correct.
Papillomaviridae is family which has non-enveloped DNA virus. They cause small papillomas. This is not a large sized virus. A single viral protein is called L1 form a capsid of 55-60 nm. Prophylactic HPV vaccines are designed with L1 protein, which is successful. Hence, the option (c) is not correct.
Hepadnaviridae: This family consists of viruses, which are enveloped. The genomes are very small and partially double stranded and partially single stranded. These viruses cause liver infections. Hepatitis B Virus is the member of this family. It is not a potential virus for vaccinations. Hence, the option (d) is not correct.
So, the poxviridae family viruses are relatively large and well suited for vaccinations and in gene therapy. Hence, the correct answer is option (b) Poxviridae.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 1SA
Smith family gets fever blisters regularly. It shows that they are infected with herpes virus. Infection takes place when the herpes virus enters the mucous membranes of lips, genital region, or through the cut on the skin. In these cases it produces oral herpes, genital herpes, and whitlow respectively.
This virus can remain dormant, for some years. In trigeminal ganglia, brachial ganglia or sacral ganglia the virus can reside in the body for several years and get activated due to stress or age, or due to immunosuppression and cause oral herpes, genital herpes and whitlow.
This recurrence is the distressing feature of this disease. Almost 2/3 of patients will experience recurrence of lesions.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 2CT
The young patient had rosy facial rash and coldlike sniffles. The Duration of the symptom was two weeks. The diagnosis of the disease, most likely may be Roseola.
The main causative organism of Roseola is Human herpes virus 6. It belongs, to the Genus is Roseolavirius.
The common symptoms of this disease are sudden fever, sore throat; enlarged lymph nodes, and rosy rash on the face; neck, trunk and thighs.
This disease got its name due to their ‘rose colored rashes.’ Thus, Rene’s sulfuring due to Roseola disease, for past two weeks.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 2MC

Most animal poxviruses are unable to infect humans because its attachment to human cells is unlikely. They are specific to the species. Their surface proteins are different. Some of the animal poxviruses like that of monkeys and sheep can infect some humans, because they have surface antigens similar to that of those animals. Hence, the option (c) is correct.
The option (a) says that affected animals are not in frequent contact with humans. This is not correct. Even if those animals are in contact with humans the poxvirus cannot attach itself to the humans as their surface protein is different. Hence, the option (a) is not correct.
The option (b) says that the human immune system makes it impossible for the foreign viral particles to reproduce effectively. This is not correct, because the attachment of the viral protein with that of human itself is not possible. So, the virus cannot enter the immune system of human. So, the option (b) is not correct.
The option (d) says that human cells lack the necessary enzyme for infection. Enzymes are used as a catalyst for any reaction. But in this case there is no attachment between the proteins and so there is any need for any enzymes to react. Hence, the option (d) is not correct.
Therefore, most animal poxviruses cannot get attached to the humans, as their surface antigens are different. Hence, the correct answer is option (c) Attachment to human cell is unlikely.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 2SA
Stocks of smallpox viruses are kept in laboratories in US and Russia. It is a research tool for investigations.
The governing body of the World Health Organization (WHO) has decided to keep the two vials of this deadly virus. They have limited any new research, with this virus till they take the next decision in 2014.
The two vials one in Georgia and one in Siberia. The Russian facility has survived several stays of execution as scientists had argument over it. So, as they have limited the research on this virus, one cannot do so till the 64^th, World Health Assembly.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 3CT
Certain features of smallpox that allowed them to be eradicated are that it is visible and can be spotted out very easily. The interval between the time of exposure and the onset of symptoms are very short.
The second feature is that it does not have animal reservoirs only humans can transmit the disease.
People who were affected developed lifelong immunity to this disease. The vaccines are highly effective. So, large number of people could be vaccinated by trained vaccinators of World Health Organization.
Hepatitis B is also a suitable candidate for eradication. Hepatitis B virus is a human pathogen. It does not have any animal reservoirs. The Hepatitis B vaccine is available and it is very effective. Hepatitis B is common in many countries. Children who are infected with this disease in their infancy suffer chronically and they excrete the virus recurrently and persistently.
The biological features, which make the disease suitable for eradication, are as follows:

First one is effective intervention that is good and effective vaccination should be available to stop the transmission of the disease.
The second one is that tools for diagnosis of the disease should be specific and sensitive, so that different levels of transmission can be detected.
The third one is human should be in the live-cycle of the agent and there should not be any animal reservoir.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 3MC

Papules are not the initial stage of lesions caused by poxvirus. Papules are second stage and it is characterized by raised sores. Hence, the option (b) is not correct.
Pustules are not the initial stage of lesions caused by poxvirus. Papules are pus filled lesions. Hence, the option (c) is not correct.
Pocks are not the initial stage of lesions of poxvirus. Pocks are also known as pustules or pox, which is pus filled lesions. Hence, the option (d) is not correct.
The poxvirus causes lesions, which have different stages. The initial stage lesions are called macules. They are flat and red skin lesions. Hence, the correct answer is option (a) macules.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 3SA
The Variola major causes severe disease with 20% or higher mortality rate. The Variola minor causes less severe disease with 1% mortality rate. This infection is also called cotton pox, alastrim and Cuban itch.
The symptoms like high grade fever (107⁰F), weakness and delirium are more debilitating in the case of Variola major. People cannot be ambulant.
In Variola minor there will be high grade fever, general weakness. But it is not as debilitating like Variola major. Patients are ambulant and due to this they may be infecting more people.
The long term effect of Variola major is severe scars on the face. The less common effects are osteomyelitis, arthritis, which causes limb deformities and blindness due to corneal ulceration and scarring. The effects of Variola minor are that they also leave scars in the skin especially on the face.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 4CT
Infection with double-stranded DNA (deoxyribonucleic acid) virus causes the symptoms. These viruses produce symptoms that of common cold.
They spread through respiratory droplets and also through drinking water, which is not chlorinated. These adenoviruses are very stable outside the body of the host and live in fomites.
The manifestations of these viruses are fever, sore throat, headache, cough, and general weakness.
Here in this case, the common source of infection may be drinking water or the water in the swimming pool, which is not properly chlorinated.
The camp management should properly chlorinate the drinking water and also the swimming pool to limit such an outbreak in future.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 4MC
The virus Variola major affects internal organs before it appears on the skin- it is a true statement.
The incubation period of this virus is 12 days. As soon as it is inhaled, it enters the oropharyngeal mucosa and enters the lymph nodes. Here, they multiply and move to other cells. There, lysis of the infected cells occurs and the virus is found in the blood stream.
The second stage in the multiplication of this virus occurs in spleen, and bone marrow. The symptoms are fever, muscle pain, and headache. There may be nausea and vomiting as the digestive system is also affected. This is called pre-eruptive stage.

After 12-15 days, lesions show up as small reddish spots in the mucosa of mouth, palates, and tongue. Skin rash appear one or two days after the lesions of mucous membrane. Macules appear first and progresses to the other stages. Hence the option (b) is correct.
The option (a) says that Variola major has less than 1% mortality. This is not correct. The mortality rate is 30-35%.
The option (c) states that Variola major has been totally eradicated from the earth. Smallpox is eradicated globally. In 1980, the WHO (world health organization) declared the eradication of smallpox globally. But stocks of this virus are still kept in labs in US and Russia. Hence, the option (c) is not correct.
The option (d) states that skin lesions caused by it are smooth, waxy, tumor like nodules on the face. This is not true. Skin lesions progress from macules to papules to vesicles and then to pus filled pustules. They are raised, round and tense, and firm lesions, which form crusts after two weeks. So, Variola major affects the internal organs before appearing on the skin.
Hence, the correct option is (b) it affects the internal organs before appearing on the skin.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 4SA
The observation that led the scientists to find the relationship between chickenpox and shingles is that Varicella-Zoster Virus. The lesions of shingles can cause chickenpox in persons, who have not had chickenpox. The Varicella Zoster Virus causes both shingles and chickenpox.
Shingles occur once or twice in a person’s life after the age of 45, unlike Herpes simplex infections which occur frequently. Before, making chickenpox vaccination as a routine vaccination in children, many children used to be affected by chickenpox and there used to be few cases of shingles.
From this, it was understood that children who develop chickenpox, develop complete immunity to Varicella Zoster Virus. They will not develop shingles in later life.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 5CT
A week after the vacation all the members of the family developed cold sores. The other names for cold sores are oral herpes and fever blisters. This infection is caused by Herpes simplex virus – Human herpes virus1. The period between the time of infection and manifestation of the disease is around two weeks.
Herpes infection is a viral infection and it is contagious. This is transmitted by close contact like kissing an infected person in that affected area. This can also be transmitted by oral sex. So, it is not a sexually transmitted disease altogether. The young children could have got that infection by kissing or by close contact.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 5MC

Cytomegalovirus in fetuses would be potentially most serious herpes virus. Transmission of this virus occurs through sexual intercourse and also from in-utero exposure, vaginal delivery, and so on. Fetuses are susceptible to severe complications of this virus. This is also called teratogenic, because it causes birth defects. When this virus attacks the stem cells in an embryo or fetus, mental retardation, visual and hearing loss, or death may result. Hence, the correct option is (d).
A whitlow is an inflamed blister. It occurs when HHV-1 or HHV-2 enter a cut in the skin of the finger. It is dangerous for the children who suck their thumbs. Health workers in gynecology, obstetrics, and dentistry should wear gloves when treating patients with herpes lesions. This is a potential source of infection, but not serious as cytomegalovirus in fetuses. Hence, the option (a) is not correct.
Ocular herpes is caused by latent herpes virus HHV-1, which affects the ophthalmic branch of the trigeminal nerve. Recurrent infection can cause corneal damage and blindness. It is not as serious as cytomegalovirus in fetus. Hence, the option (b) is not the correct option.
Shingles is called herpes zoster. It is caused by Varicella-Zoster Virus. This virus remains dormant for years. In some patients who were previously affected by chicken pox, certain conditions like stress, immune suppression, and aging reactivate the virus. These viruses travel down the nerve they occupy and produce skin rashes in the distal end of the nerves, which is very painful. This viral infection is not potentially serious. Hence, the option (c) is not correct.
So, cytomegalovirus in fetus is most potentially serious than all the other options. Hence, the correct option is (d) cytomegalovirus in fetuses.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 5SA
In countries with poor sanitation, low level of hygiene and less medical facilities, infection with Epstein-Barr (EBV) virus occurs in childhood. These infections are mostly asymptomatic because, the child has immature cellular immune system. Immature immune system cannot cause severe damage to the tissues.
In developed countries where living conditions are good and medical facilities are available, infection in the childhood does not happen rather it is in the adolescence. So, infection in later life results in severe cellular immune response and cause mononucleosis and other diseases.
In fact, cofactors also play a role in the development of diseases. In the case of Burkett’s lymphoma by Epstein – Barr virus, the infection is limited to young men who were exposed to malaria parasite. In nasopharyngeal cancer, certain cofactors in the food, genes in particular population and environment are involved.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 6MC

A man infected with adenovirus will exhibit symptoms of common cold. It includes fever, headache, cough, and pinkeye. This virus is spread by droplets and is stable outside the body. When the cells lining the respiratory tract are affected by the adenovirus respiratory symptoms are manifested. If adenovirus affects the conjunctiva, it causes pinkeye. Hence, the correct option is (e) which includes all the symptoms.
Option (a) states that the only fever is the sign and symptom of adenovirus, whereas these viruses cause fever, head ache, cough, and pinkeye. Hence, the option (a) is not correct.
Option (b) is not correct because headache is not the only symptom that is exhibited by adenovirus. Option (c) is not correct because cough is not the only symptom of adenovirus.
Option (d) is not correct because pinkeye is not the only symptom exhibited by a person infected with adenovirus.
So, all the symptoms mentioned in the options (a), (b), (c), and (d) will be exhibited by that infected person. Hence, the correct answer is option (e) all of the above.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 7MC

The inflammatory condition of the liver is called hepatitis. Hepatitis B virus causes infection in the liver. It is the only DNA (deoxyribonucleic acid) virus, which causes hepatitis. Hence, the option (d) is correct.
The option (a) is not correct. Fifth disease is also called erythema infectiosum. It is caused by parvovirus. The clinical symptoms are fever, headache, stuffy nose, and facial redness.
The option (b) is not correct. PML is progressive multifocal leukoencephalopathy caused by polyomavirus called JC (John Cunningham) virus in cases of immunodeficiency. This virus causes brain damage, which is irreversible.
The option (c) is not correct. Seed warts are caused by papillomaviruses. Papillomas found on toes or fingers are called seed warts. So, hepatitis is the inflammation of the liver. Hence, the correct option is (d) hepatitis.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 8MC

In children, Parvovirus infections are accompanied by high mortality rate is a false statement. Parvovirus is with single strand DNA (deoxyribonucleic acid) and it is the only pathogen, which affects humans. In children, fifth disease is caused by B19 virus, which is characterized by redness of skin, from the cheek and arms, thighs, and trunk. This is harmless. Hence, the correct option is (c).
B19 virus is the primary Parvovirus of humans. The statement is true. This virus belongs to genus Erythrovirus, which causes the fifth disease of erythema infectiosum. Hence, the option (a) is not correct.
Erythema infectiosum is caused by a Parvovirus is a true statement. The primary Parvovirus B19 virus in the genus Erythrovirus causes this disease. Hence, the option (b) is incorrect.
Parvovirus infection in humans’ results in infectious reddening of the skin is a true statement. This reddening of the skin starts from the cheeks. Later on, it appears on the thighs, buttocks, arms, and trunk. The rashes, which are caused by this virus, are very distinctive, so that it can be diagnosed by appearance. Hence, the option (d) is incorrect. In children, Parvovirus does not produce any harmful disease.
Hence, the correct option is (c) in children, parvovirus infections are accompanied by a high mortality rate.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 9MC

The distinguishing feature of poxvirus is its large size. The diameter is about 200 nm and the length is about 300 nm. These poxviruses are potential vectors for introducing the genetic materials in vaccinations and gene therapy due to its large size. Hence, the correct option is (a).
The poxvirus is not a polyhedral capsid. The virons are enveloped and look like a brick in shape or as a rounded brick in an oval shape. The shape varies according to the species. It is a double stranded DNA (deoxyribonucleic acid) with complex capsids and envelops. Hence, the option (b) is not correct.
The poxviruses are double stranded DNA viruses. They are with complex capsids and envelopes. So, it is not distinguished with the type of RNA (ribonucleic acid) it contains. Hence, the option (c) is not correct.
The diseases caused by poxvirus in humans are smallpox and molluscum contagiosum. In animals, it causes orf, cowpox, and monkeypox. It does not produce several types of warts. Hence, the option (d) is not correct.
So, the distinct feature of poxvirus is its large size. Hence, the correct answer is option (a) its large size.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 10MC

To prevent further risk of monkeypox infection in Zaire, we have to reinstate smallpox vaccinations for the populations of Zaire. Some scientists say that cessation of smallpox vaccinations may have increased the susceptibility to monkey pox, as smallpox vaccination also is a protection against monkey pox. So, they feel that smallpox vaccination should be reinstated in Zaire. Hence, the option (c) is correct.
Option (a) states to catch the monkeys for inoculation with monkeypox vaccine and then release them. Monkeypox is a disease not of monkeys, but of rodents and prairie dogs. Hence, option (a) is not correct.
Option (b) is incorrect because the virus does not infect only local tissues, but systems and internal organs are also affected by this infection. Moreover, it is not the possible and right way of eradication.
Option (d) is incorrect, because humans also get monkeypox by close contact with infected animals. In the past decade, there is increase in the number of persons infected with monkeypox. The reason may be a change in the viral antigen or human encroachment into monkey habitats,
Hence, the correct option is (c) Reinstate smallpox vaccinations for the population of Zaire.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 11MC

Herpesviridae family has viruses that exist in latent state in humans often. For years, they remain inactive inside the infected cells. They may get reactivated due to some factors like oldage, chemotherapy, stressful conditions, and immunosuppression. Some of this latent viruses gain entry into the chromosomes causing genetic changes and even cancers. Hence, the option (a) is correct.
Poxviridae family viruses do not show any latent stage of infection. Hence, option (b) is incorrect.
Viruses belonging to Adenoviridae family do not show this latency. Adenoviruses are one of the many causes for common cold. It is stable outside the body and survives in water, which is not properly chlorinated. Hence, the option (c) is not correct.
Parvoviridae family viruses are small in size and cause diseases, which are endemic in animals. In humans, it causes fifth disease, which is harmless. This virus does not exist in latent state in humans. Hence, the option (d) is not correct.
Herpesviridae viruses mostly exist in latent state in humans. Therefore, the correct option is (a) Herpesviridae.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 12MC

Outside the host’s body, if the envelop of a virus is unstable it would be transmitted by intimate contact. For example, poxvirus has unstable envelope outside a host’s body and it is necessary to have close contact to get infected. Hence, the option (b) is correct.
Option (a) states that the virus would be a dsRNA (double stranded ribonucleic acid) virus. This is a group of viruses, which have diversity. One example is Rotavirus; it dsRNA, but no envelope. So, this option is not correct.
Option (c) states that touching a doorknob would easily transmit it. This is not correct. By inhalation of droplets or by dried crusts, the virus can be transmitted. This infection spreads by close contact, but not by just touching a doorknob.
Option (d) states that the virus would eventually cease to be a threat to the population. This is not correct. As this virus spreads by close contact by inhalation or by crests, once it enters the host this becomes stable. So, virus with unstable envelope outside the host needs intimate contact to be transmitted.
Hence, the correct option is (b) it would be transmitted by intimate contact.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 13MC

Being habitually careful not to touch or rub eyes with unwashed hands would reduce the risk of contracting common cold. One of the causes of common cold is Adenovirus. This virus is stable outside the host and can survive in fomites and drinking water, which is not properly chlorinated. This virus spreads by respiratory droplets. Some adenoviruses cause pinkeye. Hence, the option (d) is correct.
Chickenpox is caused by Varicella zoster virus. This spreads by droplet infection by sneezing, coughing, and also by direct contact with the secretions from lesions. So, option (a) is incorrect.
Infectious mononucleosis is caused by Epstein-Barr virus. It is transmitted through saliva by sharing drinking glasses and by kissing. Initially it infects epithelial cells of pharynx and parotid salivary gland. Then it enters the blood circulations causing viremia. Hence, the option (b) is not correct.
Seed warts are caused by Papilloma virus. These are benign growth of epithelium of the skin. Papillomas found on the fingers or toes are called seed warts. It is transmitted by direct contact. As this virus is stable outside, it can spread through fomites. In the same person, it can spread form one part of the body to the other part by autoinoculation. Hence, the option (c) is not correct.
Cold spreads mainly by touching or rubbing eyes with unwashed contaminated hands. Hence, the correct option is (d) a cold.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 14MC
Human herpesvirus 2 can cause genital herpes, and infect baby at birth and causes above 10% of cold sores. This is contagious and causes most genital herpes. This virus spreads by sexual intercourse. This virus resides in the sacral ganglion and becomes latent.

When viral reactivation occurs it replicates and produces new lesions. It is seen in external genitalia, buttocks, and anus. 10% of oral herpes is due to HHV-2. 70% of the neonatal herpes is due to this virus. Hence, the option (d) is correct.
Option (a) states that human herpes virus-2 (HHV-2) can cause genital herpes. It is transmitted during child birth and it is cause for 70% of neonatal herpes. It produces cold sores also. Hence, the option (a) is not correct.
Option (b) states that this virus may infect a baby at birth; the baby is infected at birth when it comes in contact with these lesions in the birth canal. Neonatal infections are serious, causing 80% of mortality if the virus affects the central nervous system. If it is oral or only skin lesions, the mortality rate is 30%. This is not the only manifestation of this virus. So, the option (b) is incorrect.
Option (c) states that HHV-2 causes 10% of cold sores; these are itchy, painful skin lesions, which occur on the lips. The presence of HHV-2 in the oral lesions and HHV-1 in the genital area may result due to oral sex. In severe infections, lesions go down to the oral cavity. This is not the only manifestation of this virus. Hence, this option is not correct.
So, Human herpes virus 2 causes genital herpes, infect a baby at birth, causes 10% of cold sores. Hence, the correct option is (d) all of the above.

Microbiology with Diseases by Taxonomy Chapter 24 Answers 15MC

Herpesvirus is latent and can reactivate to cause further disease. They stay inactive inside the infected cells even for years. It can be reactivated by old age, stressful conditions, chemotherapy, and immune-suppression. Sometimes, this virus may enter into the chromosomes and cause genetic changes also. Hence, the option (a) is correct.
Papillomavirus is not latent. It causes papillomas on the skin or mucous membrane. It is also called warts. Seed warts, flat warts, genital warts are some of the types of warts caused by this virus. Hence, option (b) is not correct.
Adenovirus is not latent. This is one of the causes of common cold. It is transmitted by respiratory droplets and through drinking water, which is not properly chlorinated. Hence, option (c) is not correct.
Parvovirus is not latent. It is the only single stranded DNA, which infects humans. It is small in size. It causes many endemic diseases in animals. In humans, it causes fifth disease or erythema infectiosum. Hence, the option (d) is not correct.
Herpesvirus is latent and gets reactivated by factors like old age, stressful conditions, and immune-suppression. Hence, the correct option is (a) Herpesvirus.

Microbiology with Diseases by Taxonomy Chapter 24 Answers

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