India and prophylaxis of malaria: the issue can be tricky for the doctor making the counseling Traveller . How to provide clear recommendations and evidence-based? From whom derive the information for counseling?
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The recommendations from international and governmental agencies have important differences with regard to malaria prophylaxis for travelers to India.
The following table compares the recommendations of WHO and some major Western nations.
| Source | mode of performing a prophylactic malarial for India | Reference | |
| Pharmacological | Only antivettoriale | ||
| WHO | in all malarious areas of the country (recommended different medications depending on the area) | no | (1) |
| CDC - Centers for Disease Control and Prevention ( | in all areas malaria in the country | no | (2) |
| Health Protection Agency (United Kingdom) | in high risk areas and risk variable | in low-risk areas (some countries of South and North India) | (3) |
| DTG - Deutsche Gesellschaft für Tropenmedizin und Internationale Gesundheit (Germany) | no | associated with the stand-by treatment (presumptive treatment of emergency) in all areas of potential risk | (4) |
| Public Health Agency of Canada | in all malarious areas of the country | no | (5) |
should also be noted that a survey of European experts from TropNetEurop has shown, on this specific topic of prophylaxis malarial for India, a significant divergence of views (6).
What is the actual magnitude of the risk for travelers to India?
WHO figures show, since 1992, a declining trend of malaria cases in the Indian population from 260 to 180 cases per 100,000 inhabitants, except for a peak of 335 - 345/100.000 in 1995 - 1996, to coincide with events in epidemic ( 7). The epidemiological situation however is not uniform in the area, where coexist incidence areas of low, intermediate and high and regular outbreaks occur, as happened in 2006 - 2007 in Goa (8.9) and 2010 in Mumbai (as evidenced by reports of the news www.promedmail.org).
WHO data related to morbidity and mortality due to malaria in India been called into question, since according to some authors, the existing surveillance in the country underestimate the magnitude of the phenomenon, which has been raised about the concept of "India's malaria burden invisible" (10).
If we turn our attention to cases of malaria in travelers returning from India we can see that, despite a considerable increase in tourist numbers occurred in recent decades, reaching 3.92 million admissions in 2005, the incidence of imported malaria has decreased. A study published in 2009 provides the following data (7):
- incidence in travelers: decrease from 90 cases per 100,000 in 1992 to 20 cases per 100,000 in 2002;
- 80% of the cases it was Plasmodium vivax malaria ;
- considering instead the only cases of Plasmodium falciparum , this accounts for a minority fraction of cases among travelers, averaging 10 to 13%;
- as demonstrated for other destinations, most of the cases of import about people of Indian origin belonging to type VFR (Visiting Friends and Relatives ), that immigrants are visit relatives and friends in the country of origin.
A decrease in the incidence in travelers had already been highlighted in a 2006 study, based on data from the network TropNetEurop, even this study shows a low percentage of cases P. falciparum, 13% (11).
What consequences arise from the predominance of Plasmodium vivax in India?
The commonly used anti-malarial prophylaxis in preventing recurrent infections by P. vivax. This type of Plasmodium is different from P. falciparum, and is able to establish a latent infection through the hypnozoites, particular forms of P. vivax dormant in the liver, they are not destroyed by common anti-malarial activity against the blood stage of malarial parasite. The dormant forms of P. vivax can survive despite chemoprophylaxis, and re-emerge, causing symptoms of the disease, even months after returning from the trip.
Although, among the various anti-malarial, atovaquone + proguanil (Malarone) is able to exert an effect on the dormant forms of P. vivax, it proved not to be able to eliminate them and therefore will not prevent relapsing vivax malaria (12). The commonly used anti-malarial prophylaxis instead have a high efficacy in preventing malaria by P. falciparum. In any case, although a vivax malaria is usually a clinically less severe falciparum malaria, so that it was called benign tertian in reality is not so benign, they can produce complications such as respiratory distress, kidney failure, jaundice, rupture spleen and other (12).
direct the traveler to India must always make the chemoprophylaxis of malaria?
We have some clues to answer this question:
a) the incidence of malaria in travelers from India is not high;
b) the species most frequently implicated is P. vivax;
c) the drugs currently used in chemoprevention do not prevent the later onset of malaria by P. vivax;
d) in some parts of India the risk of malaria, including that from P. falciparum, is consistent, while in others it is very low;
s) in India can occur flares epidemic of malaria, falciparum and vivax is.
Based on these data, the answer to this question is negative: the travelers to India should not always make the chemoprophylaxis of malaria. It is for the health expert on Travel Medicine, on the basis of a constant updating of the local epidemiological situation and on the basis of the peculiar characteristics of the individual traveler (such as medical history, itinerary, accommodation) to assess whether to recommend prophylaxis medication. Aid may come from consulting the map available on the website of Travel Medicine of the Health Protection Scotland. The site, belonging to the Scottish Public Health Service, reports to every nation a constantly updated map of malaria risk for travelers and, for each level of risk, suggesting that intervention could be implemented.
Bibliography
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4th German Society of Tropical Medicine and International Health. Recommendations for malaria prevention. As of March 2010. Available from:
5th Public Health Agency of Canada . Canadian Recommendations for the Prevention and Treatment of Malaria Among International Travellers. CCDR 2008; 34S3 :1-45. Available from:
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9. Jelinek T, on behalf of the European Network on Imported Infectious Disease Surveillance (TropNetEurop) . Continuing importation of falciparum malaria from Goa into Europe . Euro Surveill. 2008;13(5):pii=8028. Available from: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=8028
10. Hay SI, Gething PW, Snow RW. India 's invisible malaria burden. The Lancet, Volume 376, Issue 9754, Pages 1716 - 1717, 20 November 2010.
11. Behrens RH, Bisoffi Z, Björkman A, Gascon J, Hatz C, Jelinek T, Legros F, Mühlberger N, Voltersvik P. Malaria prophylaxis policy for travellers from Europe to the Indian Subcontinent. Malar J ,2006;5(--):7. Available from: http://www.malariajournal.com/content/5/1/7
12. Chen LH, Wilson ME, Schlagenhauf P. Controversies and misconceptions in malaria chemoprophylaxis for travelers. JAMA ,2007 May 23;297(20):2251-63. Available from:
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