Sir--In their excellent Seminar on measles (March 1, p 763),¹ Trevor Duke and Charles Mgone divide the fight against the disease into three battles: control, outbreak prevention, and eradication. Since control and outbreak prevention should result from large-scale immunisation, a better way to divide the battle might be into individual protection (from disease), control (of disease or of infection), elimination (of infection), and eradication (of infection).

 

Even where the incidence of measles is high, endemicity is high, and immunisation coverage low, a properly vaccinated child is protected. With increasing immunisation coverage, the disease will be brought under control; incidence of disease and of infection will be reduced, and outbreaks prevented or delayed. When transmission of infection is interrupted in countries or continents, as in Finland, most countries in the Americas, Australia, etc, the term elimination applies. Elimination of transmission of infection worldwide is eradication.

 

Duke and Mgone agree that measles meets the fundamental criteria for eradication, as did smallpox and polio, but caution that "global eradication might be impossible in reality and could cripple the health services of some very low-income countries."¹ I disagree; we should aim to eradicate measles. Measles is not only more devastating than polio, which affected much lower numbers of children than measles kills each year, but would be easier to eradicate. More than ten doses of polio vaccine per child and almost 100% coverage was needed to interrupt poliovirus transmission in many poor countries, whereas only two doses of measles vaccine--which could easily be fitted into the routine childhood immunisation programme--are needed for its elimination.

 

The surveillance and vaccination infrastructure and expertise used to fight polio should be applied to measles without delay after polio eradication. I hope the new Director-General of WHO will resolve to take this initiative. When the World Health Assembly resolved to eradicate polio, only the Americas had eliminated the infection. Measles virus transmission has been eliminated in more countries already, so the feasibility of eradication is greater than it was for polio. If polio can be eradicated, measles can be, indeed must be, eradicated too.

T Jacob John

 

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439 Civil Supplies, Godown Lane, Kamalakshipuram, Vellore, TN 632 002, India (e-mail:vlr_tjjohn@sancharnet.in)

 

 

1 Duke T, Mgone CS. Measles: not just another viral exanthem.  Lancet  2003; 361: 763-73. [Text]

 

Sir--Our experience indicates that the comprehensive international approach to measles control proposed by Trevor Duke and Charles Mgone¹ can be readily implemented and is highly effective. Over the past 2 years, the Measles Initiative (http://www.measlesinitiative.org), consisting of international organisations and African countries with high measles disease burden working together, has adopted the sustainable measles mortality reduction strategies recommended by WHO and UNICEF. These include two opportunities for immunisation, surveillance, and improved clinical management of measles cases.² In developing countries, the first opportunity for immunisation is usually offered through routine immunisation services and the second through periodic campaigns.

 

In 2001 and 2002, the Measles Initiative helped to implement these strategies in 19 African countries, resulting in the vaccination of more than 70 million children against measles. The effect has been similar to that seen in the Americas--every country is reporting a greater than 75% reduction in measles deaths. The WHO regional office for Africa estimates that the annual measles death rate in Africa has been reduced by about 100000 deaths as of February, 2003, representing a 22% decline from the peak of 452000 estimated annual deaths in 2000. In 2003, the initiative hopes to lend its support to 14 countries, vaccinating more than 80 million children and preventing an additional 167000 annual deaths.

 

The WHO-UNICEF vaccination strategy is demonstrably effective and is broadly applicable. In six of seven countries of Southern Africa, measles deaths have been reduced to extremely low levels and sustained for longer than 3 years despite high rates of HIV-1 infection, regular measles importation from neighbouring countries, disruption of health services, and drought. The strategy is effective even in countries with modest levels of routine immunisation delivery. For example, Mali, with an estimated 37% routine coverage of measles vaccine among 1 year olds, reported a 93% decline in cases after a campaign. By contrast, wealthy countries that have not fully implemented these strategies continue to have outbreaks. For example, Japan, with routine single-dose coverage of 81%, reported 32890 measles cases in 2000. Italy, with 70% routine single-dose coverage, had an outbreak in 2002 in the Campania region with more than 20000 cases, resulting in 13 cases of encephalitis and three deaths from measles.^3,4

 

We strongly disagree with Duke and Mgone on the need to have different strategies for measles control and outbreak prevention "at different times and in different places". The WHO-UNICEF strategy is being used to eliminate measles virus circulation in the Americas and to reduce measles deaths to near zero in Africa. Differences in outcome can be attributed to programmatic aims and intensity of strategy implementation, not to any limitation of the strategy itself. To sustain these mortality reductions, second opportunity immunisation will have to be available for all future cohorts of children until measles is eradicated. Global measles eradication could ultimately depend on use of additional strategies, but increased implementation of the current strategy is a necessary starting point.

*M Grabowsky, P Strebel, A Gay, E Hoekstra, B Hersh

 

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*American Red Cross National Headquarters, 2025 E Street NW, Washington, DC 20006, USA (MG); and Centers for Disease Control and Prevention, Atlanta, USA (PS); United Nations Foundation, Washington, DC, USA (AG); UNICEF, New York, USA (EH); and WHO, Geneva, Switzerland (BH) (e-mail:grabowskym@usa.redcross.org)

 

 

1 Duke T, Mgone CS. Measles: not just another viral exanthem.  Lancet  2003; 361: 763-73. [Text]

 

 

2 WHO/UNICEF. WHO-UNICEF joint statement on strategies to reduce measles mortality worldwide. http://www.unicef.org/pubsgen/measles-statement/measles-statement.pdf (accessed April 28, 2003).

 

 

3 Anon. Measles, Japan, 1999-2001.  IASR  2001; 22: 273-74. [PubMed]

 

 

4 Ciofi degli Atti M, D'Argenio P, di Giorgio G, Grandori L, Filonzi A. Measles in Italy 2002. Eurosurveillance Weekly 2002. http://www.eurosurveillance.org/ew/2002/021205.asp#5 (accessed April 28, 2003).