Effect of artesunate-mefloquine fixed-dose combination in malaria transmission in Amazon basin communities

Background

Studies in South-East Asia have suggested that early diagnosis and treatment with artesunate (AS) and mefloquine (MQ) combination therapy may reduce the transmission of Plasmodium falciparum malaria and the progression of MQ resistance.

Methods

The effectiveness of a fixed-dose combination of AS and MQ (ASMQ) in reducing malaria transmission was tested in isolated communities of the Juruá valley in the Amazon region.

Priority municipalities within the Brazilian Legal Amazon area were selected according to pre-specified criteria. Routine national malaria control programmatic procedures were followed. Existing health structures were reinforced and health care workers were trained to treat with ASMQ all confirmed falciparum malaria cases that match inclusion criteria. A local pharmacovigilance structure was implemented. Incidence of malaria and hospitalizations were recorded two years before, during, and after the fixed-dose ASMQ intervention. In total, between July 2006 and December 2008, 23,845 patients received ASMQ. Two statistical modelling approaches were applied to monthly time series of P. falciparum malaria incidence rates, P. falciparum/Plasmodium vivax infection ratio, and malaria hospital admissions rates. All the time series ranged from January 2004 to December 2008, whilst the intervention period span from July 2006 to December 2008.

Results

The ASMQ intervention had a highly significant impact on the mean level of each time series, adjusted for trend and season, of 0.34 (95%CI 0.20 – 0.58) for the P. falciparum malaria incidence rates, 0.67 (95%CI 0.50 – 0.89) for the P. falciparum/P. vivax infection ratio, and 0.53 (95%CI 0.41 – 0.69) for the hospital admission rates. There was also a significant change in the seasonal (or monthly) pattern of the time series before and after intervention, with the elimination of the malaria seasonal peak in the rainy months of the years following the introduction of ASMQ. No serious adverse events relating to the use of fixed-dose ASMQ were reported.

Conclusions

In the remote region of the Juruá valley, the early detection of malaria by health care workers and treatment with fixed-dose ASMQ was feasible and efficacious, and significantly reduced the incidence and morbidity of P. falciparum malaria.

Serologic testing for symptomatic coccidioidomycosis in immunocompetent and immunosuppressed hosts

Serologic studies are an important diagnostic tool in the clinical evaluation and follow-up of persons with coccidioidomycosis. Numerous types of serologic tests are available, including immunodiffusion, enzyme immunoassay, and complement fixation. We conducted a retrospective review of the results of 1,797 serologic tests spanning 12 months from the onset of coccidioidomycosis in 298 immunocompetent and 62 immunosuppressed persons with symptomatic infection. Using the onset of symptoms as a reference point, we plotted the positive or negative serologic results over time for both groups. Compared with the immunocompetent group, immunosuppressed persons had lower rates of seropositivity for every type of test during the first year after onset of symptoms for coccidioidomycosis, although many results did not achieve statistical significance. Combining the results of these tests increased the sensitivity of the serologic evaluation in immunocompromised patients. Immunosuppressed persons have the ability to mount a serologic response to coccidioidomycosis, but in some circumstances, multiple methods may be required to improve detection.

Coccidioidomycosis in patients with diabetes mellitus

PURPOSE

The study reviewed the interrelationships of diabetes mellitus and coccidioidomycosis.

SUBJECTS AND METHODS

We conducted a retrospective review of the medical records of immunocompetent patients with coccidioidomycosis who were treated at our academic medical institution between January 1, 1999, and October 31, 2003, to compare those with and without diabetes mellitus and to determine whether glycemia correlates with the course of illness.

RESULTS

Of 329 immunocompetent patients with coccidioidomycosis, 44 had diabetes (4 type 1 and 40 type 2) and were divided into 2 groups: those with serum glucose concentrations of less than 12.2 mmol/L (220 mg/dL) and those with glucose concentrations of greater than or equal to 12.2 mmol/L (220 mg/dL). Persons with diabetes in either glucose group were more likely than those without diabetes to have cavitary lung disease (relative risk, 2.94; P<.001) and relapsed infection. However, only the diabetes group with serum glucose concentrations greater than or equal to 12.2 mmol/L (220 mg/dL) were more likely to have disseminated infection (relative risk, 2.8; P=.05) and to require treatment (relative risk, 9.85; P=.005), but their infection was less likely to resolve (relative risk, 0.24; P=.002).

CONCLUSION

Because glycemia strongly correlated with clinical characteristics of coccidioidomycosis in this cohort, we recommend routine measurement of serum glucose in persons with coccidioidomycosis to identify patients with an increased risk of complicated infection. Future studies should evaluate the efficacy of tight glycemic control on the outcome of coccidioidal infection.