This is also known as varicella and it derives its name from the positive agent that is the varicella-zoster virus. This disease is acute in nature, highly contagious, and can spread from one person to another fast and is characterized by a vesicular itchy rash. This rash spreads very quickly to all parts of the body and is associated with constitutional symptoms like malaise and fever which occur in most of the viral infections. This is a disease that is seen commonly in children caused by the varicella-zoster virus. It is characterized by mild headache, fever, malaise, and eruption of blisters on the skin and mucous membrane. It is extremely rare to see someone getting chickenpox infection more than once.
As we know that chickenpox vaccine was introduced in the mid-1990s since then we have seen the cases to be declining. The varicella-zoster virus (VZV) causes chickenpox infection. We see most of the cases occur through contact with an infected person. The virus is contagious to those around you for 1 to 2 days before your blisters appear. VZV remains contagious until all the blisters crust over. The mode through which the virus can spread is coughing, sneezing, saliva, and contact with fluid from the blisters. The hallmark symptoms for chickenpox is a rash. Before the rash appears there will be a general feeling of being unwell or malaise. Fever is usually worse in adults than in children. The persons feel aching in the muscles, there is a loss of appetite, whereas in some cases there is a feeling of nausea. After the rash appears the severity from a few spots to a rash that covers the whole body. The spots developed in clusters and generally appear on the face, limbs, chest, and stomach. They tend to be small, red, and itchy.
Blisters can develop on the top of the spot, these can become very itchy. If we take the time for about 48 hours the blisters cloud over and begin drying out, there is a crust developed. The crusts fall off on their own within 10 days of time. During the whole cycle, a new wave of spots can appear. Considering such a case, we will see the patient can have different clusters of spots with different stages of crustiness, dryness, and itchiness. Other symptoms, where a few people have more severe symptoms. If the following occurs a doctor should be contacted. If we observe the skin around the spots or blisters it becomes more painful and red, and some experience breathing difficulties. Most healthy individuals make a full recovery as with cold or flu by resting and drinking plenty of fluids. The doctor or nurse will know whether a child or adult has chickenpox just by looking and asking a few questions. No medical tests are required to aid in the diagnosis, on rare occasions chickenpox may be confused with scabies or some type of insect bites. If you have a fever your doctor may recommend antipyretics. If you seem to appear dehydrated and unable to consume fluids your doctor may recommend IV fluids either in an emergency room or as a hospitalized patient.
The case of secondary bacterial skin infections may be treated with antibiotics. Because a virus causes chickenpox, no antibiotics can cure the disease. Tep or pat but don’t scratch the itch caused by this, take a cool oatmeal bath which you will be able to get at your local drug store, dap or pat, but don’t rub your skin dry. It is advised to wear loose cotton clothing that will help your skin to breathe. Heat and sweat will make you itch more, use a cool wet washcloth on the super itchy areas to calm your skin. Drink lots of fluids to help your body rid itself of the virus faster, it also helps you from getting dehydrated.
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The epidemiology of chickenpox is as follows
- This occurs worldwide.
- In temperate climates, it mostly affects children less than10 years of age.
- However, in tropical climates, the epidemiology of chickenpox is less well understood. As it’s not only the children but young adults who seem to be affected which is very common.
- When we talk about the non-immune travelers, that is those who have not suffered from chickenpox or those who have not been vaccinated have a high risk of acquiring the infection if they are traveling to a zone that is highly endemic for chickenpox.
Let us first look at the agent, the causative organism which is varicella-zoster virus. It belongs to the subfamily alphaherpesvirus. This virus has got the prediction for nerve root ganglia. Once the virus acquires the virus it will go and produce primary and secondary viremia. This virus will then remain dormant attached to the nerve root ganglia. In the future, if the immune system of the person is compromised, this virus can get reactivated to what we call as causing zoster or shingles and it mostly occurs in adults. Because the virus has become dormant and it gets reactivated. So chickenpox and zoster are 2 different hosts’ responses to affection by the single agent that is varicella-zoster virus.
As discussed earlier it affects children that are primarily less than 10 years of age. A person having an attack of chickenpox that means suffering from the symptoms and signs of chickenpox. In general, they will not have a second attack, as one attack will provide a durable immunity. What is important is if a pregnant woman suffers from varicella-zoster infection it’s likely that her unborn fetus is also at risk of suffering from chickenpox. The severity of the disease in terms of the appearance of the rash as well as all the symptoms is much more if the person acquires chickenpox infection in adulthood.
Overcrowding and seasonal variations are 2 important considerations. Overcrowding in places with ill ventilation is going to allow the transmission of the virus from one person to the other. In tropical areas mostly there are seasonal variations, so at times when there are very cold people prefer to stay indoors. Here what will happen is the prevalence of infection will increase.
Chain of Infection
First consider a reservoir, a person who is suffering from chickenpox. We can say as the case who can transmit the agent to the susceptible host, the person who has not acquired the infection and the way or the mode of transmission of the virus to the susceptible host is mainly through direct droplet infection which is through aerosols through activities like coughing, sneezing or talking through which aerosols are generated and they can be transmitted from reservoir to the susceptible host. Another mode of transmission is through direct contact, Now the direct contact is the way of transmission whereby the vascular fluid which contains the virus if it comes in contact with the skin of the susceptible host it can cause transmission of the virus to the susceptible host. There is one more mode of the transmission of the virus to the susceptible host and that is through indirect contamination of the articles used by the case or the person suffering from the chickenpox. If this article is touched or used by the susceptible host immediately after the virus has been acquired on that particular object it can result in infection, but it is a less common mode of transmission. We have to remember that indirect spread is also possible through contaminated articles or what we call as fomites. Generally, when we consider the spread of infection from the reservoir to the susceptible host, we consider this as person to person spread. So directly through activities like coughing, sneezing, or the direct contact of the vascular fluid the virus can be transmitted to the susceptible host.
Chickenpox is considered in 2 stages because we said that this is an exanthem, as because this is a disease characterized by rash we have the pre-eruptive stage and the eruptive stage
- The pre-eruptive stage is the stage before the rash appears and it is characterized by symptoms like fever, malaise, back pain. Which lasts for about 24 hours, this generally is for children. However, this prodromal stage lasts for a longer period which is around 2 to 3 days and it is quite severe. The person will not be able to get up, he will be having very high fever and malaise.
- Eruptive stage means the appearance of the rash. As far as children are concerned they would show up with a rash vest as the first sign. This rash would come up immediately after the fever comes in most of the cases.
Characteristics of The Rash
Understanding the rash of the chickenpox is very important, as we need to differentiate this rash from other conditions in which the rash is present.
- The rash of chickenpox is symmetrical in nature; it will occur on both sides around the body.
- It first appears on the trunk and then spreads to the face, arms and legs.
- Axilla is affected in most of the cases of chickenpox.
- Pals and soles are seldom affected.
- This rash has got the predilection for the flexor surface of the body more than the extensor surface of the body.
- When we look at the rash of chickenpox in a person, it will show you all the stages advancing from macule, papule, vesicle, and scab.
- This is because the rash quickly advances through all these stages and secondly it occurs in crops. So there are crops of the eruption of the rash which occur because of which we can see all the stages of rash at one time in one individual. This characteristic of the rash of chickenpox is known as the pleomorphism or pleomorphic of the nature of the rash.
Once the virus gains entry into the body of the susceptible host It will take around 14 to 16 days until the appearance of the rash. But it has been observed that the incubation period can be as wide as 10 to 20 days.
Period of Infectivity
- 1 to 2 days before the appearance of the rash and 4 to 5 days thereafter. What is important here is the vesicular fluid is one of the modes of transmission for the virus.
- Once the lesions get crushed or scar formation occurs, the person will no longer remain infected because it is only the vesicular fluid that contains the virus. Once the vesical phase goes away the virus is not going to be there in the rash.
These are very important as the person who gets complications of chickenpox has a higher mortality rate than the person who recovers from chickenpox. Generally, this disease is self-limiting and usually goes off on its own. However, in people who have got low immunity or low immune status, it can have a secondary bacterial infection. So the common complication which may occur mainly in children is
- Pneumonitis or encephalitis, invasive group A streptococcal infection. streptococcal infection in itself can cause a lot of problems for the child with reference to nutrition and immunity.
- This virus is going to remain latent in the neural ganglia and upon subsequent reactivation, the varicella-zoster virus can cause shingles or zoster which affects mainly immunocompromised individuals or elderly individuals. This is another complication which we consider to be chickenpox.
- Maternal varicella can cause fetal wastage, there can be abortion or if the child is born it will have birth defects if the mother has suffered from chickenpox.
The control of chickenpox involves
- Notification of the cases.
- Isolation of the case for about 1 week after the onset of the rash to cover the period of communicability.
- Disinfection of articles that are soiled by the nasal and the throat secretions of the infected person.
- Symptomatic management of cases, antivirals have also been used to manage the case of chickenpox, mainly Acyclovir is used so that the case is treated and the complications are prevented. Those who get complications like streptococcal infection antibiotics may have to be used in order to achieve control of the disease.
We have 2 areas in which we need to discuss one is passive immunization and the other is active immunization.
- Passive immunization is achieved with the help of varicella-zoster immune globulin also known as VZIG It is indicated for using highly susceptible VZV exposed immunocompromised or immunosuppressed populations.
- The high-risk groups considered having low immune status are
- Immunocompromised adults and children.
- Newborns of mothers with varicella shortly before and after delivery.
- Premature infants.
- Infants are less than 1 year of age.
- Adults without evidence of immunity.
- Pregnant women.
- VZIG is recommended to be administered within 72 hours of exposure.
- The intramuscular route of administration.
- This is archived by the varicella-zoster vaccine.
- This is a live attenuated vaccine.
- Recommended for active immunization.
- Single-dose for healthy children aged between 12 to 18 months and 2 doses in 4 to 8 weeks interval in susceptible people older than 13 years.
- The effectiveness of the vaccine wanes over time ranging from 97 % in the first year after vaccination and to 84 % at 8 years post-vaccination.
FAQ (Frequently Asked Questions)
- Is The Chickenpox Contagious For Health?
Most people are contagious a day before the symptoms appear and remain contagious as long as the symptoms persist which generally takes about a week. The only people at risk of contracting chickenpox are those who have never had it before. The pool of possible infection is significantly low with other conditions. The infected people should avoid public areas to be careful to keep their distance from those who have never been infected.
- Why Should We Not Use Aspirin On Children To Treat Chickenpox or Flu?
Even though aspirin is approved in Childers older than 2 years old, use with chickenpox or the flu can increase the risk of developing a serious condition known as Reye’s syndrome. Reye’s syndrome can damage important organs like the brain or liver and can even be fatal.