November 4 (HealthDay News) -- Snakebites pose an important but neglected threat to global public health, new research claims.

The comprehensive study, published in this week's PLoS Medicine, estimates that at least 421,000 poisonings and 20,000 deaths from snakebites occur annually, while suggesting the numbers could be as much as four times greater.

Places of particular concern are sub-Saharan Africa and South Asia where anti-venoms are hard to obtain. India has the highest estimated annual poisonings and deaths: 81,000 and 11,000, respectively.

In an accompanying "Perspective" article in the publication, Jean-Philippe Chippaux, from the Institut de Recherche pour le Dveloppement in La Paz, Bolivia, called the situation of anti-venom availability and cost in Africa dire. He noted the current global economic crisis could make it worse, as a vial of anti-venom costs the equivalent of several months of income for most rural families.

The estimates, done by researchers from University of Kelaniya in Sri Lanka, are based on a thorough review of the scientific literature, mortality data from United Nations' databases, unpublished information, and interviews with snakebite experts. The researchers concluded that further population-based studies of poisonings and death from snakebites are needed.

SOURCE: PLoS Medicine, news release, Nov. 3, 2008