Maternal systemic or cord blood inflammation is associated with birth anthropometry in a Tanzanian prospective cohort

OBJECTIVES

HIV infection is associated with chronic systemic inflammation, with or without antiretroviral therapy. Consequences for foetal growth are not understood, particularly in settings where multiple maternal infections and malnutrition are common. The study was designed to examine maternal systemic circulating and umbilical cord blood cytokine concentrations in relation to birth anthropometry in a Tanzanian prospective cohort.

METHODS

A 9-plex panel of maternal plasma cytokines in HIV-positive (n = 44) and HIV-negative (n = 70) mothers and the same cytokines in umbilical cord blood collected at delivery was assayed. Linear regression modelled associations between maternal or cord blood cytokines and birth anthropometry.

RESULTS

Health indicators (haemoglobin, mid-upper-arm circumference, body mass index) in HIV-positive mothers without considerable immunosuppression did not differ from HIV-negative women. Despite this, HIV-exposed infants had lower birthweight and length. Subgroup analyses indicated that HIV management using HAART was associated with lower plasma TNF-α, as were longer durations of any antiretroviral therapy (≥2 months). Greater maternal plasma TNF-α was associated with earlier delivery (-1.7 weeks, P = 0.039) and lower birthweights (-287 g; P = 0.020), while greater umbilical cord TNF-α (-1.43 cm; P = 0.036) and IL-12p70 (-2.4 cm; P = 0.008) were associated with shorter birth length. Birthweight was inversely associated with cord IL-12p70 (-723 g; P = 0.001) and IFN-γ (-482 g, P = 0.007). Maternal cytokines during pregnancy did not correlate with umbilical cord cytokines at delivery.

CONCLUSIONS

Systemic inflammation identified in maternal plasma or umbilical cord blood was associated with poorer birth anthropometrics in HIV-exposed and HIV-unexposed infants. Controlling maternal and/or foetal systemic inflammation may improve birth anthropometry.

Patterns of malaria related mortality based on verbal autopsy in Muleba District, north-western Tanzania

Reliable malaria related mortality data is important for planning appropriate interventions. However, there is scarce information on the pattern of malaria related mortality in epidemic prone districts of Tanzania. This study was carried out to determine malaria related mortality and establish its trend change over time in both epidemic and non-epidemic areas of Muleba District of north-western Tanzania. A verbal autopsy survey was conducted to obtain data on all deaths of individuals who died in six randomly selected villages from 1997 to 2006. Relatives of the deceased were interviewed using a standardized questionnaire. Communicable diseases accounted for about two thirds (61.9%) of deaths among > or =5 years individuals and 84.8% in < or =5 years. Non-communicable diseases accounted for 28.9% and 14.1% deaths in > or =5 years and < or =5 years, respectively. Malaria was the leading cause of deaths in all age groups (40.3%) and among children <5 years (73.8%). Infants accounted for about two third (64.5%) of all malaria related deaths in children <5 years. Peak of malaria proportional mortality was highest during malaria epidemics. Most of the malaria-related deaths in this group were among 1-12 months (64.5%) followed by 13-24 months (20.9%), and 25-59 months (14.8%). Cerebral malaria accounted for 18.9% (N=32) of death related to malaria in all age groups; 12.1% (17/141) were in under-five, 42.9% (6/14) were in 5-14 years and 64.3% (9/14) in 15-70 years old. More than half of malaria related deaths (61.0%) in <5 years children were associated with severe anaemia followed by diarrhoeal disease (24.1%), cerebral malaria (12.5%) and respiratory infection (8.5%) as common conditions. The majority of the deceased caretakers first sought treatment at health facilities within 24hr of the onset of illness. Significantly a higher proportion of caretakers of the underfives in the epidemic area sought treatment within 24hr than in non-epidemic area (39.3% vs. 18.5%; P = 0.0385). In conclusion, malaria accounts for majority of deaths in Muleba district, with substantial proportion being attributed to malaria epidemics.

Knowledge, attitudes and practices on tsetse and sleeping sickness among communities living in and around Serengeti National Park, Tanzania

A study was undertaken to investigate knowledge, attitudes and practices about sleeping sickness (human African trypanosomiasis) among communities living in and around Serengeti National Park (SENAPA). Structured questionnaires were administered to a total of 1490 consenting participants. Of the respondents, 924 (62%) knew sleeping sickness, and 807 (87.3%) knew the right place to seek healthcare. Of 924 who knew sleeping sickness, 386 (42%) said the disease was present in the areas they live. Most respondents (85.4%) knew that sleeping sickness infections were acquired in the bush and forest. The most common (69.3%) sources of information about sleeping sickness were relatives and friends. Symptoms of sleeping sickness mentioned included abnormal sleep (45.2%), fever (35.3%), body malaise (14.5%), headache (7.6%) and lymph node enlargement (6.1%). Of 1490 people interviewed 90.4% knew tsetse flies and 89.8% had been bitten by tsetse flies. The majority (86.6%) of the respondents knew that sleeping sickness is transmitted through a tsetse bite. Activities that exposed people to tsetse bites included working in tsetse infested bushes/forests, grazing livestock in tsetse infested areas and hunting game animals. In conclusion, communities living in and around SENAPA were knowledgeable about tsetse and sleeping sickness. The communities can thus understand and support community based tsetse and sleeping sickness control programmes to ensure success.

Glossina dynamics in and around the sleeping sickness endemic Serengeti ecosystem of northwestern Tanzania

We investigated the dynamics of Glossina spp. and their role in the transmission of trypanosomiasis in the sleeping sickness endemic Serengeti ecosystem, northwestern Tanzania. The study investigated Glossina species composition, trap density, trypanosome infection rates, and the diversity of trypanosomes infecting the species. Tsetse were trapped using monopyramidal traps in the mornings between 06:00 to 11:00 and transported to the veterinary laboratory in Serengeti National Park where they were sorted into species and sex, and dissected microscopically to determine trypanosome infection rates. Age estimation of dissected flies was also conducted concurrently. Tsetse samples positive for trypanosomes were subjected to PCR to determine the identity of the detected trypanosomes. Out of 2,519 tsetse trapped, 1,522 (60.42%) were G. swynnertoni, 993 (39.42%) were G. pallidipes, three (0.12%) were G. m. morsitans, and one (0.04%) was G. brevipalpis. The trap density for G. swynnertoni was between 1.40 and 14.17 while that of G. pallidipes was between 0.23 and 9.70. Out of 677 dissected G. swynnertoni, 63 flies (9.3%) were infected, of which 62 (98.4%) were females. A total of 199 G. pallidipes was also dissected but none was infected. There was no significant difference between the apparent densities of G. swynnertoni compared to that of G. pallidipes (t = 1.42, p = 0.18). Molecular characterization of the 63 infected G. swynnertoni midguts showed that 19 (30.2%) were trypanosomes associated with suid animals while nine (14.3%) were trypanosomes associated with bovid animals and five samples (7.9%) had T. brucei s.l genomic DNA. Thirty (47.6%) tsetse samples could not be identified. Subsequent PCR to differentiate between T. b. brucei and T. b. rhodesiense showed that all five samples that contained the T. brucei s.l genomic DNA were positive for the SRA molecular marker indicating that they were T. b. rhodesiense. These results indicate that G. swynnertoni plays a major role in the transmission of trypaniosomiasis in the area and that deliberate and sustainable control measures should be initiated and scaled up.