What is Measles?
What is Measles? It is also called rubeola. The mortality of measles varies greatly in different parts of the world. In India, it is a major cause of morbidity and a significant contributor to childhood mortality.
It is 100 to 400 times more likely to cause death in a preschool child of a developing country than it is in the US and Europe. In developing countries, case fatality rates range from 2 to 15 percent as compared to less than 0.2 per 10,000 notified cases in developed countries.
Before the vaccine became available in the 1960s, measles has killed about 7 to 8 million childrenâs a year and caused an estimated of about 135 million cases a year worldwide. Today, it still kills about one million children of the estimated 30 million who get measles.
Thus this disease remains a number one killer among vaccine-preventable diseases of childhood, taking its toll primarily among underfed kids whose natural defenses are weakened by different infections
It is an acute disease and is a highly infectious disease of childhood which is caused by a specific virus of the group myxoviruses. It is clinically characterized by the presence of fever and catarrhal symptoms of the upper respiratory tract in the form of coryza, cough, and presence of a typical rash.
Causes for suffering from the Measles
Agent:- Measles is caused by an RNA paramyxovirus. There is only one serotype of this virus. This virus cannot survive outside the human body for any length of time but retains infectivity when stored at sub-zero temperature.
Starting of infection:- Those people who are suffering from the measles are the only source from where infection can start. Measles carriers (those who carry measles virus in themselves and spread the virus) are not present. In some evidence it was shown that there were some subclinical cases of measles are present.
Infective Material:- Secretions of the nose, throat and respiratory tract of a case of measles during the prodromal period and the early stages of the rash can spread more infection.
Transmission of disease:- During its first stage i.e., its prodromal period, measles is highly infectious for its direct or indirect transmission especially when the measles eruption is about to start appearing.
With the decline of the eruption phase, the transmission period of this disease also declines, which means at that time it is not highly infectious as in the prodromal period.
Time of starting and declining of rashes that is 4 days before and 5 days after the appearance of the eruption is highly risk period of transmission of disease. So to prevent its transmission isolation of the patient was done for about one week prior starting of the rash.
Secondary attack rate:- There is only one antigenic type of measles virus. Once the Infection appears it covers lifelong immunity. Most supposed secondary attacks represent errors in designation either in initial or second malady.
Who is susceptible?
Age:- Measles affects virtually everyone in infancy or childhood- between 6 months and 3 years of age in developing countries because of poor environmental conditions. While children who are over the age of 5 years are affected in developed countries.
Immunity:- No age is immune if there was no previous immunity. One attack of measles generally confers life-long immunity. Second attacks are rare.
Nutrition:- Nutrition plays an important role as measles appeared in a malnourished child is having more risk of health and mortality rate is even more which carries about 400 times higher than those childrenâs who are well-nourished and suffered from measles.
The most common cause for their high risk of health is due to poor cell-mediated immunity response of their body and due to malnutrition.
It was seen that severely malnourished children have shown to excrete virus for a longer period than better-nourished children.
Immune compromised patients like HIV or AIDS, immune-suppressive patients, those patients in which organ or stem cell transplant has done and those patients who are under steroid therapy are more at the high risk for measles.
Role of Environment in the spread of the virus
Though the virus can spread in all the seasons in winters this disease is more likely to spread. Gathering of the people in the house which makes the virus to get transfer very easily.
In India viruses usually spread between January to April month that is during winters and in early spring.
So it can be concluded that it can be easy spreads where the population density is high.
How this virus gets transmitted?
The virus gets the entrance in the body through the respiratory tract. Transmission occurs directly from person to person mainly by droplet infection and droplet nuclei.
This occurs from 4 days before the onset of rash until 5 days thereafter. Infection can transmit through conjunctiva is also considered.
The incubation period is commonly 10 days from the exposure to onset of fever, and 14 days to the appearance of the rash
Symptoms of Measles
Symptoms are categorized under three stages:-
Prodromal stage:- This stage starts 10 days after the infection and lasts until 14 days. Symptoms found are:-
- Coryza with sneezing and nasal discharge
- Redness of the eyes
- Diarrhea or vomiting
- Appears of rash Koplikâs spots in the buccal mucosa (Koplikâs spots are small, bluish-white spots on a red base, smaller than the head of a pin)
- Appears of typical, dusky-red, macular or macula-papular rash which begins behind the ears and spreads rapidly in a few hours over the face and neck. It extends down the body taking 2 to 3 days to progress to the lower extremities.
- Disappears of fever in another 3 to 4 days is signaling of the end of the disease.
- The rash fades in the same order of appearance leaving a brownish discoloration which may present for 2 or more than 2 months.
- Loss of weight
- Growth retardation
- Cancrum oris
- Pyogenic infection
- Reactivation of pulmonary tuberculosis
- Deterioration of health
Laboratory investigation for confirmation of measles virus was confirmed by the presence of positive measles IgM antibodies and virus isolation measles virus from the respiratory tract.
For those patients who are not willing to give a blood sample. Their investigation can be done through saliva for salivary measles-specific IgA antibodies test.
Common complications are:-
- Associated diarrhea
- Other respiratory diseases
- Otitis media
With this, there are some serious complications are also present which are related to neurology:-
- Febrile convulsions
- Sub-acute sclerosing pan-encephalitis (SSPE)
It is advised that severe case measles in the area of high fatality rate, they should first get treated with vitamin A because most of the children develop an acute deficiency of vitamin A which is reflected in form of keratomalacia and blindness from corneal scarring.
Treatment of Measles
Today measles can be prevented by active immunization in the form of vaccination. This vaccination is done at the age of nine months as recommended by WHO.
For those areas where the outbreak of measles is present than the vaccination can give at the age lowered to 6 months. This vaccine is administered in a single subcutaneous dose of 0.5 ml and it should be kept on ice and used within one hour.
After administration of the vaccine, the child may have an illness (fever and rash) which may subside between 1 to 3 days.
For reducing fever and pain anti-pyretic and painkillers are advised. For those patients who have difficulty in breathing fast acting, medication is given to dilate the bronchi for breathing and it helps to reduce the cough
Few of the individual may get some adverse effects of this vaccination. In which the Toxic shock Syndrome (TSS) is one of the important.
It occurs when the measles vaccination was contaminated or the same vial was used for more than one session on the same day or the next day.
The vaccine must be used within 4 hrs after opening. TSS can be preventable but once it occurred the person shows poor immunity. The symptoms of TSS are:-
- Severe watery diarrhea
- High fever
These symptoms appear within a few hours of administration of infected vaccines. If not treated immediately death within 48 hours present.
The measles vaccine is mostly given as a combineâs vaccine with other live attenuated vaccines such as mumps and rubella vaccines known as the MMR vaccine. This combination is highly effective.
To prevent from spreading, the following control measures have been recommended:-
The person has to keep isolated for 7 days after the onset of rash.
Those patients who are in contact with the diseased one should be immunized within two days of exposure and if person vaccination is contraindicated due to any cause than immunoglobin must be given within 3-4 days of exposure of the measles virus.
Lastly but not the least an epidemic immunization is essentially done at the beginning of the diseases to prevent the spreading of the disease in that area.
Even after effective strategy done for immunization to prevent the measles cases, outbreak still occurs, especially in those areas where the population is very dense, urban slum, even after good coverage.
This happens because of vaccine efficacy which about 85% and childrenâs with measles was poorly immunized previously.
Measles can also be prevented by the administration of immunoglobulin (human) early in the inoculation period. The dose of immunoglobulin is decided by WHO which is 0.25 ml per kg of the body weight.
It should be kept in mind that this dose should be given within 3-4 days of exposure.
So for prevention, supplementary vaccination campaigns should be conducted in several countries with the follow-up, targeting to eliminate measles morbidity and mortality reduction.
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