A BRIEF DESCRIPTION OF MEASLES: A VACCINE PREVENTABLE DISEASE
By Oluchi Anita Chukwuka Ogbu
Measles is a highly contagious disease caused by a virus in the paramyxovirus family of the genus Morbillivirus. It is one of the leading causes of death among children globally especially in developing countries, regardless of effective and safe vaccine that have been made available (World Health Organization, 2015). In 2014, WHO recorded that it led to the death of about 114,900 people worldwide of which majority was children under five, although this have decreased since the invention of vaccine. Thus, the number of global measles cases reported to the United Nation Children’s fund (UNICEF) and to the WHO between 2000 and 2008 reduced by 67%. At the same time, the measles global death reduced by 78% (Cairns et al., 2011). Since 2008, outbreak has been occurring globally but the most reported cases of measles have persistently been from Africa (Centers for Disease Control and Prevention, 2011).
The rationale of this paper is to analyze the viral disease using the basic epidemiological concepts. This will be illustrated by looking at the stages of the viral disease, the prevention and control measures using the epidemiological triad.
SIGNS AND SYMPTOMS/STAGES
High fever that usually last for 4 to 7 days is typically the first sign of measles. Other sign and symptoms include; cough, watery nose, watery and red eye etc. Rashes erupt after several days especially on the upper neck and face. It then spreads to other parts of the body which last for about 5 or 6 days before it fade (WHO, 2015).
Incubation period The incubation period of measles is about 7 to 18 days. It takes up to 14 days before the rash appear. The infected host can be highly infectious during this incubation period (Nishiura, 2007).
Latent period- This is period between contact with the infectious agent and the start of infectiousness. This is about 4 to 5 days .It can happen during the incubation period. Thus, it is shorter than the incubation period (Nishiura, 2007).
This shows that before the clinical manifestation of the disease, the carrier can actually infect others, that is why measles virus is highly infectious especially among those that are highly at risk ( CDC,2011).
TRANSMISSION and WHO IS AT RISK?
The transmission of measles virus is mainly from the spread by the airborne route and from one person to another through infected throat and nasal secretion. It is one of the known viral diseases that are very contagious with >90%seconadry attack rate in susceptible institutional and household contacts (WHO, 2015; CDC, 2011). Therefore, anybody who is not protected from the virus is at risk of getting infected (CDC, 2011).
PREVENTION AND CONTROL
Epidemiological triad of measles
Host- the only host for this contagious virus are humans (white et al., 2012). The key public health strategy in controlling measles is routine measles vaccination at individual level which is usually done between the ages of 8 months and one year (WHO, 2015). This can also be seen as a primary prevention of the disease outbreak. Mass immunization campaign can be done at population level to prevent or reduce further global measles death. The World health Organization recommended two doses of vaccine to ensure immunity and for the prevention of outbreak because one may not develop immunity from the first dose (WHO, 2015).
Those that are already infected with the measles virus can also be isolated from others to control cross infection (CDC, 2011)
Environment- overcrowded environment, countries with poor health infrastructure. Maintaining a proper personal and community hygiene is important in preventing the spread of measles.
Disease causing agent- measles is caused by the virus of genus Morbillivirus in the paramyxovirus family.
The measles virus is best prevented by the measles, mumps and rubella (MMR) combination vaccine of the measles, mumps, rubella and varicella (MMRV) combination vaccine.
There is no antiviral treatment that is specifically for measles virus that exists. It can only be managed through supportive care which ensures proper intake of fluid, good nutrition and primary prevention of dehydration that can be done using the oral rehydration solution recommended by WHO. (WHO, 2015).
Measles is still one of the leading deaths globally despite the availability of vaccine. Coughing, sneezing and direct contact with the infected are some of the ways in which it is transmitted. Prevention and controlling of the spread of this contagious disease is imperative as there is no known treatment for measles infection.
Cairns, K. L., Perry, R. T., Ryman, T. K., Nandy, R. K., & Grais, R. F. (2011). Should outbreak response immunization be recommended for measles outbreaks in middle-and low- income countries? An update. Journal of Infectious Diseases, 204(suppl 1), S35-S46.
Centers for Disease Control and Prevention (CDC. (2011). Measles outbreaks and progress toward measles preelimination—African region, 2009-2010. MMWR. Morbidity and mortality weekly report, 60(12), 374.
Nishiura, H. (2007). Early efforts in modeling the incubation period of infectious diseases with an acute course of illness. Emerging themes in epidemiology, 4(1), 1.
Orenstein, W. A., Perry, R. T., & Halsey, N. A. (2004). The clinical significance of measles: a review. Journal of Infectious Diseases, 189(Supplement 1), S4-S16.
White, S. J., Boldt, K. L., Holditch, S. J., Poland, G. A., & Jacobson, R. M. (2012). Measles, mumps, and rubella. Clinical obstetrics and gynecology, 55(2), 550.
World Health Organization (2015). Measles. Retrieved on 15/03/2015 from http://www.who.int/mediacentre/factsheets/fs286/en/