SENSITIVITY OF MICROSCOPY COMPARED TO MOLECULAR DIAGNOSIS OF P. FALCIPARUM: IMPLICATIONS ON MALARIA TREATMENT IN EPIDEMIC AREAS IN KENYA

Detection of Plasmodium species by microscopy has been the gold standard for diagnosis of malaria for more than a century. Despite the fact that there is a significant decline in the number of positive cases reported from microscopy, anti-malarial drugs prescriptions are on continuous increase as patients present with symptoms of malaria. This makes it difficult to establish accuracy, sensitivity and specificity of light microscopy in diagnosis of malaria in epidemic areas. This study was designed to compare microscopy with polymerase chain reaction as diagnostic methods for malaria in three epidemic areas in Kenya. A total of 356 patients presenting with malaria symptoms were diagnosed by microscopy and dried blood filter paper spots were collected from patient in Kisii, West Pokot and Narok districts. Plasmodium falciparum DNA was extracted from the dried blood filter samples. Primers specific for the Plasmodium Species were designed and used in a two step amplification of the Pfmdr gene. The PCR products were analyzed in ethidium bromide stained 1.5% agarose gel. It was found that 72 out of 350 specimens diagnosed as negative were positive for P. falciparum by nested PCR, while 6 which were microscopy positive were confirmed so by nested PCR. This study demonstrates that there is a high level of misdiagnosis which may either lead to denial for deserved treatment or undeserved treatment. Nested PCR detection of malaria parasites is a very useful complement to microscopy although it is expensive and takes long time. Additionally, smear negative patients suspected to have malaria should be subjected to PCR diagnosis to improve rational drug use. The economic burden of misdiagnosis and mistreatment of malaria outweighs that of PCR diagnosis, hence this diagnostic mode could be tenable in the long run even in rural areas

Sea urchin reduction as a restoration technique in a new marine park

Coral reefs degraded from heavy fishing may require both fisheries management and habitat manipulation in order to promote desired species of fishes and corals. High population densities of sea urchins is a common form of reef degradation and this study compares two efforts to determine the effects of sea urchin reduction on reef ecology. These experiments were undertaken after protection from fishing to determine if sea urchin reduction combined with reduced fishing would promote the recovery of hard corals and finfishes. Experiments were done at two scales, a small (- 50 m x 50 m) area studied for one year and a large (100 m x 100 m) area studied for three years. Both experiments found increases in fleshy algae, estimates of total finfish wet weights, and particularly parrotfish, wrasses and scavengers biomass after the manipulation. Changes in fish Wet Weights were smaller in the large compared to the small scale experiments which suggests a dilution effect with the increasing spatial scale of the manipulation. The small scale manipulation produced a loss while the large scale manipulation produced an increase in hard coral cover. In both cases this appeared to be caused by an initial rapid increase in fleshy algae during the first 200 days of the experin1ent. Afterwards, fleshy algae decreased and hard coral increased. The decrease in fleshy algae and increase in hard coral were probably attributable to increased herbivory and seasonal storms. The eventual Joss of algae combined with reduced sea urchin grazing promoted hard corals. Sea urchin reduction after the cessation of fishing is a useful reef restoration technique but requires fishing restrictions and time to promote coral recovery

Sea urchin reduction as a restoration technique in a new marine park

Coral reefs degraded from heavy fishing may require both fisheries management and habitat manipulation in order to promote desired species of fishes and corals. High population densities of sea urchins is a common form of reef degradation and this study compares two efforts to determine the effects of sea urchin reduction on reef ecology. These experiments were undertaken after protection from fishing to determine if sea urchin reduction combined with reduced fishing would promote the recovery of hard corals and finfishes. Experiments were done at two scales, a small (- 50 m x 50 m) area studied for one year and a large (100 m x 100 m) area studied for three years. Both experiments found increases in fleshy algae, estimates of total finfish wet weights, and particularly parrotfish, wrasses and scavengers biomass after the manipulation. Changes in fish Wet Weights were smaller in the large compared to the small scale experiments which suggests a dilution effect with the increasing spatial scale of the manipulation. The small scale manipulation produced a loss while the large scale manipulation produced an increase in hard coral cover. In both cases this appeared to be caused by an initial rapid increase in fleshy algae during the first 200 days of the experin1ent. Afterwards, fleshy algae decreased and hard coral increased. The decrease in fleshy algae and increase in hard coral were probably attributable to increased herbivory and seasonal storms. The eventual Joss of algae combined with reduced sea urchin grazing promoted hard corals. Sea urchin reduction after the cessation of fishing is a useful reef restoration technique but requires fishing restrictions and time to promote coral recovery

Sea urchin reduction as a restoration technique in a new marine park

ABSTRACT Coral reefs degraded from heavy fishing may require both fisheries management and habitat manipulation in order to promote desired species of fishes and corals. High population densities of sea urchins is a common form of reef degradation and this study compares two efforts to determine the effects of sea urchin reduction on reef ecology. These experiments were undertaken after protection from fishing to determine if sea urchin reduction combined with reduced fishing would promote the recovery of hard corals and finfishes. Experiments were done at two scales, a small (~ 50 m x 50 m) area studied for one year and a large (100 m x 100 m) area studied for three years. Both experiments found increases in fleshy algae, estimates of total finfish wet weights, and particularly parrotfish, wrasses and scavengers biomass after the manipulation. Changes in fish wet weights were smaller in the large compared to the small-scale experiments which suggests a dilution effect with the increasing spatial scale of the manipulation. The small-scale manipulation produced a loss while the large-scale manipulation produced an increase in hard coral cover. In both cases this appeared to be caused by an initial rapid increase in fleshy algae during the first 200 days of the experiment. Afterwards, fleshy algae decreased and hard coral increased. The decrease in fleshy algae and increase in hard coral were probably attributable to increased herbivory and seasonal storms. The eventual loss of algae combined with reduced sea urchin grazing promoted hard corals. Sea urchin reduction after the cessation of fishing is a useful reef restoration technique but requires fishing restrictions and time to promote coral recovery