Approximately 90% of the population resides on the coastal belt, a seven, or so mile wide strip of low-lands running the length of Guyana's Atlantic frontier. Here, malaria posed a major public health problem during and before the first half mark of the twentieth century. Anopheles darlingi proved an excellent vector for local malaria transmission and posed a formidable challenge until the advent of the Malaria Eradication Campaign in 1947.
Inset Map Shows the current approximate distribution of Anopheles aquasalis
( Yellow Areas) and Anopheles darlingi (Green) in Guyana At present
Based on the intra-domiciliary residual spraying of the new product D.D.T, egining in 1942 or so, the elimination of the A. darlingi from the coast, was attained in a matter of a few years. In 1960 this strip of densely populated territory attained the eradication category of maintenance phase area. Only one out-break of malaria was detected during 1961 along the estuary of the demerara river. This was quickly controlled.
The interior regions were sparsely populated by some 40
- 70,000 indigenous amerindian residents West Indian immigrants and some
"coastlanders" ( guyanese who moved to the interior from the
coast or those who had businesses in the interior ) who had established
small settlements. ( inset map showing malaria areas in 1945
and in 1969 when it was limited to narrow fronteir area bordering Brazil.)
There the situation was quite different and the attack
phase of the campaign started in the decade of 1960. It was based on some
residual spraying of DDT, mass blood survey, active and passive case detection
and a chloroquinized salt campaign, attaining a reduction of transmission
. In 1973 seroepidemiological studies, (Lobel et al 1976) indicated no
recent transmission in Region VII/VIII, and part of Region l. 
Transmission
was then limited to a narrow strip of fronteir territory in Region 9 ,
and Brazil, state of Roraima. 
Since 1960, however, outbreaks were reported in the North
West Region (Region 1) in 1966. The Cuyuni-Mazaruni (Region V11) in 1966-67
and Rupununi (Region 1X) in 1972. In fact, even though, positive cases
detected, fell to only 42 cases in 1973, the Rupununi seems to be the point
from which the relapse of malaria transmission began in 1975. 
The Coast
On the coastal belt the situation is precarious. Since the eradication campaign came to a close in 1958 with the elimination of the A. darlingi, the ecological and entomological status of the coastal belt has changed considerably, (Giglioli 1963). In 1958, it was noted that the A. aquasalis a secondary vector of malaria was present, but that this vector was primarily zoophyllic (Giglioli 1938).
In 1961 A. aquasalis was responsible for a small outbreak in Demerara. Since the interruption of barrier spraying in 1958 (Lobel et al 1976) no accurate information on the Anophiline fauna on the coast has been available. This situation is compounded by the constant importation of malaria to the coast from interior regions a definite reversal of trends suggested by Lobel et al in their 1973 serological studies, when malaria was imported to the interior from the coast.
In fact a number of malaria cases have been detected and
classified as being autochthonous to the coastal regions.And cases have
been detected in the capital Georgetown, and surronding areas. Inset
map shows Distribution of locally transmitted malaria cases in georgetown
from 1988 to 1994
.
Further on, the East Canje area of Region V1 has also
been implicated in some level of local . Inset map shows local malaria
cases on the coastal belt 1988-1994.
The fact that the entomological status is not fully known
with importation of cases from the interior, two assumptions must be made,
that the coast is both vulnerable and susceptible to the re-establishment
of some level of transmission.
L Validum MD Last updated Sept 22 1998
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