extramural researchers in the basic and clinical sciences and is the only federal entity that actively supports basic research on tropical diseases.

Consistent with overall NIAID and NIH funding patterns, about 20 percent of all tropical disease research monies are spent in-house, with most of the remainder going to U.S. investigators outside NIH through a competitive grants award system. Grants from NIAID to foreign investigators for tropical disease research are relatively rare. Out of a total FY 1989 budget of $831 million, NIAID allocated $8.3 million (1 percent) to malaria (Table 3-4). While funding for tropical diseases as a proportion of the overall NIAID budget has declined over the past four years (largely because of the rapid influx of AIDS research funding), funding for malaria as a proportion of tropical diseases has increased. The bulk of NIAID extramural malaria research support during FY 1987 through FY 1989 went to studies on vaccines and immunity, while research on parasite biology received the next largest share of funds (Figure 3-4).

Overall, the U.S. government has invested nearly $140 million on malaria research and control activities over the past four years (Table 3-5). More than half of that amount was spent by USAID.