Treatment of worm infections leads to increases in CD4 counts and haemoglobin and fall in viral load for HIV-positive women taking ART

De-worming is associated with falls in viral load and increases in CD4 count and haemoglobin, in pregnant women living with HIV and receiving antiretroviral therapy (ART), according to the results of a study conducted in Rwanda and published in the online edition of Clinical Infectious Diseases. Albendazole – a cheap treatment for helminth infections – was provided to 980 women.

Albendazole was provided on a targeted and non-targeted basis, and the investigators showed “both these treatment modes were equally effective.” They suggest, “in regions endemic for geohelminths, non-targeted anthelmintic therapy may be more cost effective than a test-and-treat procedure.”

Soil-transmitted helminth infections are endemic in many of the regions hardest hit by HIV. In sub-Saharan Africa, an estimated 22 million people are co-infected with helminths and HIV.

Both malaria and worm infections are known to contribute to HIV disease progression. An international team of investigators therefore wanted to see if treatment of helminth infections was beneficial for HIV-positive pregnant women taking ART. Haemoglobin, viral load and CD4 count were monitored pre- and post-partum. Analyses were also conducted to determine helminth treatment strategies: specifically, whether treatment should be targeted to women with laboratory-confirmed worm infections, or whether it could be given to all patients.

Study participants were recruited from antenatal clinics. All were in the second trimester of pregnancy and none had previously received helminth therapy.

The participants were divided into two groups: 467 received targeted helminth therapy when stool samples were positive; 513 received therapy at all time points. Women were given anti-malarials when malaria-positive.

Prevalence of helminth infections at baseline was as follows: A. lumbricoides, 21%; T. trichiura 7%; hookworm, 6%. Approximately 9% of women in the targeted treatment group were co-infected with helminths and malaria, compared to a co-infection prevalence of 5% in the non-targeted group.

In both groups, CD4 counts increased significantly, reaching a peak at the final study visit. CD4 counts were significantly higher in the non-targeted versus the targeted group (p < 0.05).

In both groups, the proportion of women with a detectable viral load fell significantly during the study (non-targeted: 9 to 5%, p < 0.05; targeted: 9 to 4%, p < 0.005).

Haemoglobin levels also increased significantly in both the study arms.

Sub-group analysis that looked at outcomes according to helminth infection status confirmed that targeted and non-targeted use of albendazole was equally effective.

“The current study demonstrates that in pregnant women receiving ABZ [albendazole] therapy, CD4 counts increase, whilst detectable viral loads decrease in the presence of concurrent ART,” comment the authors. “ABZ therapy significantly augments ART in improving immune function and blocking viral replication. Furthermore, haemoglobin levels increase significantly after de-worming.”

They conclude, “within regions where geohelminths are endemic, non-targeted intervention may be more effective than targeted approach.”