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An anopheline mosquito surveillance was conducted in the malaria endemic areas of Utan Rhee and Lunyuk counties, eastern Sumbawa Island, in 2004 and 2005. Eight species of Anopheles were collected, including a new record of An. balabacensis on the island.

Field trials on the spatial repellency of metofluthrin-impregnated plastic strips for mosquitoes present in shelters without walls (beruga) were carried out in Lombok, Indonesia. A major reduction in the incidence of human biting by Culex quinquefasciatus was achieved, and the use of two strips per beruga repelled >60% of the mosquitoes for at least 11 wk while four strips repelled >60% of the mosquitoes for more than 15 weeks. The technique was found to be a practical long-term solution for the prevention of mosquito bites without using electricity or heat to evaporate the metofluthrin.

Trials of metofluthrin-impregnated multilayer paper strips against mosquitoes in shelters with no walls were carried out at 3 sites in Lombok, Indonesia. Major reductions in human biting by Culex quinquefasciatus, Anopheles balabacensis, and An. sundaicus were achieved. The device is a very practical measure of preventing outdoor mosquito biting, with no need for electricity or heating to evaporate its active ingredient.

Spatial repellency of a new multilayer paper strip impregnated with metofluthrin, a newly synthesized pyrethroid, was evaluated in the laboratory and in the field at Kerandangan, Lombok Island, Indonesia, with the use of cow- and human-baited double nets. Spatial repellency was observed in both cow- and human-baited collections. Metofluthrin treatment reduced mosquito collection by >80% during the 1st 4 weeks. However, repellency seemed to reduce with the loss of metofluthrin by evaporation within 6 wk after treatment.

Medical and entomological surveys were conducted to determine the risk factors of Plasmodium falciparum and P. vivax infections on Lombok Island, Indonesia, to find the risk factors and the main mosquito vectors for each malaria. Multivariate longitudinal analysis demonstrated two significant risk factors for infection with P. falciparum: disappearance of P. vivax parasitemia (p<0.001) and a specific study site (p<0.001). In contrast, younger age (p=0.024) and the interpolated virtual density of An. subpictus (p=0.041) were significantly associated with increased risk of infection with P. vivax. Thus, it seems that the distribution of P. vivax was determined largely by the presence of An. subpictus, whilst that of P. falciparum was influenced by antagonism with P. vivax. This result shows the importance of following-up treated P. vivax patients to identify recrudescence of P. falciparum in this area.

Remote Sensing (RS), a Global Positioning System (GPS) and a Geographic Information System (GIS) were used to analyze relationship between Anopheles subpictus larval densities and environmental parameters in the Sekotong district on Lombok Island, Indonesia. Distance from the coast to larval habitats, season and surface water were considered as environmental parameters for determining An. subpictus larval densities. Japanese Earth Resources Satellite (JERS) Visible and Near Infrared Radiometer (VNIR) satellite imagery for the area acquired by National Space Development Agency of Japan (NASDA) were used to detect water, which could be used to characterize larval habitats. Data on larval sampling sites obtained from a GPS were entered into a GIS for mapping larval habitats to measure distance between the coast and the larval habitats. A GIS was used for overlaying of data coverages (i.e., water distribution from RS data and larval habitats coupled with data on larval densities) to identify factors that may explain the spatial distribution patterns of larval densities. An. subpictus larval densities were significantly associated with season and distance from the coast to larval habitats. The rainy season and the distance from the coast to larval habitats were critical environmental determinants for presence of An. subpictus larvae in the study. In this paper, we investigated relationship between An. subpictus larval densities and the environmental parameters using RS/GPS/GIS to determine if these tools could be used to predict larval densities.

Anophelesflavirostris (Ludlow) from Lombok Island, Indonesia, was crossed with An. minimus species A (CM strain) from Thailand and species E (ISG strain), a new sibling species, from Japan, to determine genetic compatibility. We also compare the scanning micrographs of female cibarial armature of these three species. Both An. minimus CM and ISG females crossed with An. flavirostris males produced eggs without embryos. One An. flavirostris female crossed with an An. minimus CM male deposited unhatchable eggs with an 18% embryonation rate. The scanning micrographs of the cibarial armature clearly show significant differences among An. flavirostris and the two sibling species of the An. minimus complex. These results support the specific status of An. flavirostris. Previous records of An. minimus Theobald in this country are also discussed.

Larval density of Anopheles sundaicus in shaded and unshaded fish farming ponds was monitored at a coastal village in North Sumatra, Indonesia. The average density in the experimentally shaded ponds with Nipa leaves was reduced to < 1/10. Disappearance of algae and decline of water temperature also were observed, but the salinity did not change. The larval density was lower in ponds with Tilapia sp than without fish, but that in ponds with Ophiocephalus sp was not significantly lower. Dominant insects collected by dipping were Agrionidae and Libellulidae (Odonata), Corixidae, Notonectidae and Nepidae (Hemiptera), and Dytiscidae (Coleoptera). Density of nymphs of both Odonata and Notonectidae was higher in unshaded ponds. Taking into account longevity of the materials, and easiness in construction and applicability, shading by Nipa leaves was an easy and effective larval control measure against A. sundaicus in non-operating small fish farming ponds if leaves were renewed once in every two months.

A survey of infectious coryza of chickens was performed in West Jawa of Indonesia between 1987 to 1988 by the detection of hemagglutination-inhibition (HI) antibody against Haemophilus paragallinarum (Hpg) in non-vaccinated healthy laying (12 farms, 196 chickens) and native (8 farms, 197 chickens) chickens. HI antibodies against Hpg were detected not only in the native chickens but also in the laying chickens, regardless of the district, and were observed in 70% (14/20) of farms and 19% (73/393) of chickens. HI antibodies against serotype A were detected from 11 farms (55%) and 11% (45/393) in chickens. Those against serotype C were detected from 5 farms (25%) and 8% (30/393) in chickens. Three Hpg strains were isolated from different chickens affected with infectious coryza. Two of them were identified as type A and the other as type C by the rapid plate agglutination test. These results demonstrated that the outbreaks of infectious coryza caused by serotype A and C strains had occurred in Indonesia.