Tropical bloom-forming mesoalgae Cladophoropsis sp. and Laurencia sp.-responses to ammonium enrichment and a simulated heatwave.

Algal blooms are increasing worldwide, driven by elevated nutrient inputs. However, it is still unknown how tropical benthic algae will respond to heatwaves, which are expected to be more frequent under global warming. In the present study, a multifactorial experiment was carried out to investigate the potential synergistic effects of increased ammonium inputs (25 μM, control at 2.

Spatial and seasonal distribution of cyanobacteria Moorea species in coastal waters of Tanzania.

This study aimed at identifying the presence of harmful cyanobacteria, detecting potential harmful algae toxins and their distribution in three seasons: December to February (hot dry season), March to May (rainy season), and June to November (cool dry season) of 2016. The samples were collected in five study sites in Tanzania: Tumbe, Chwaka, Paje, Bweleo in Zanzibar islands and Songosongo Island, mainland Tanzania, where skin irritation problems were observed in seaweed workers in an earlier study. The cyanobacteria from the Moorea genus were microscopically detected in the seawater, with highest concentrations in the months with the highest seawater temperature or hot dry season, than in the other two seasons.

A new Progressive Management Pathway for improving seaweed biosecurity.

The rapid expansion and globalization of the seaweed production industry, combined with rising seawater temperatures and coastal eutrophication, has led to an increase in infectious diseases and pest outbreaks. Here, we propose a novel Progressive Management Pathway for improving Seaweed Biosecurity.

An international evaluation of biosecurity management capacity in the seaweed aquaculture industry.

Seaweeds form the second largest global aquaculture product in volume, and despite rapid growth of the sector over the last 25 years, production and quality in top producing regions is becoming increasingly limited due to disease and pest outbreaks, the spread of non-native cultivars and the degradation of genetic health due to inbreeding. Most notably, the lack of biosecurity measures leading to disease and pest outbreaks are reported to cause the most significant production losses in the seaweed industry. This study uses the Knowledge, Attitude and Practice (KAP) survey tool to quantify and compare biosecurity cross-culturally, in two major red seaweed producing countries, the Philippines and Tanzania.

Isolation of the Tephrosia vogelii extract and rotenoids and their toxicity in the RTgill-W1 trout cell line and in zebrafish embryos.

This study focused on identifying the rotenoids from the Tephrosia vogelli plant (fish-poison-bean), investigating the toxic potency of a crude T. vogelii extract and individual rotenoids (tephrosin, deguelin and rotenone) in vitro and in vivo and assessing the mode of action. A trout (Onychorynhis mykiss) gill epithelial cell line (RTgill-W1) was used to determine the cytotoxicity of rotenoids and effects on cell metabolism.

Malaria control at the district level in Africa: the case of the muheza district in northeastern Tanzania.

An assessment was done in Tanzania to determine the extent to which the primary health care services have contributed to reducing the burden of malaria since the system was initiated in the 1980s. Seven descriptive processes and outcome indicators of effectiveness were used: changes of malaria transmission and incidence over time; use of facility-based care services for malaria; patients' access to professional advice; the trend of treatment failure over time of sulfadoxine-pyrimethamine and chloroquine; survival rates of severe cases at the district hospital; a district malaria control strategy; number of malaria specific training for care providers; and the number of activities carried out on mosquito control measures. The data were collected from 1996 to 2003 in the Muheza district northeastern Tanzania.

Mutations in dhfr in Plasmodium falciparum infections selected by chlorproguanil-dapsone treatment.

Treatment with the novel antifolate drug combination chlorproguanil-dapsone effectively cleared asymptomatic Plasmodium falciparum infections in 246 (93.5%) of 263 children in the Usambara Mountains of Tanzania during the course of a 2-week follow-up. Samples from 71 recurrent infections, collected over a 9-week follow-up, showed selection for parasites with the triple mutant Ile(51)-Arg(59)-Asn(108) in dihydrofolate reductase.

A trial of proguanil-dapsone in comparison with sulfadoxine-pyrimethamine for the clearance of Plasmodium falciparum infections in Tanzania.

Considerable levels of resistance to sulfadoxine-pyrimethamine (SP) have been reported in Plasmodium falciparum in north-eastern Tanzania, and the identification of a suitable antimalarial to replace SP is now a high priority. We conducted a trial in July 2000 to determine the efficacy of proguanil (PG) plus dapsone (DS), compared with that of SP, for the treatment of asymptomatic falciparum infection. A total of 220 children with parasitaemia > or = 2000 per microL completed the study; 112 had received a single dose of SP (dosage calculated for pyrimethamine 1.

The effects of house spraying with DDT or lambda-cyhalothrin against Anopheles arabiensis on measures of malarial morbidity in children in Tanzania.

The effects of house spraying of DDT and lambda-cyhalothrin against populations of Anopheles arabiensis were assessed in children aged between 1 and 10 years with regard to fever episodes and parasite prevalences. DDT and lambda-cyhalothrin treatment did not reduce the prevalence of malaria episodes as defined by fever (temperatures > or = 37.4 degrees C and/or fever reported) combined with high parasitaemia (> or = 100 parasites/200 leucocytes).

Trial of pyrethroid impregnated bednets in an area of Tanzania holoendemic for malaria. Part 4. Effects on incidence of malaria infection.

Groups of about 30 children in each of five villages were given pyrimethamine-sulfadoxine to clear their malaria parasitaemia, and they were followed up with fortnightly blood slides. Parasitaemia returned rapidly in the absence of vector control, but more slowly when pyrethroid impregnated nets were in use or the houses had been sprayed with DDT. Variation between the incidence of malaria infection in these cases seemed to depend more on ecological or social factors than on the particular form of vector control adopted.

Trial of pyrethroid impregnated bednets in an area of Tanzania holoendemic for malaria. Part 3. Effects on the prevalence of malaria parasitaemia and fever.

Children aged 1-10 in five villages were contacted fortnightly. Their axillary temperatures, reports of fevers and blood slides were taken. Following the introduction of permethrin impregnated nets into two estate villages the slide positivity for falciparum malaria declined markedly.