The Impact of Intensive Versus Standard Anthelminthic Treatment on Allergy-related Outcomes, Helminth Infection Intensity, and Helminth-related Morbidity in Lake Victoria Fishing Communities, Uganda: Results From the LaVIISWA Cluster-randomized Trial
Authors: Sanya Richard E , Nkurunungi Gyaviira , Hoek Spaans Remy , Nampijja Margaret , O’Hara Geraldine , Kizindo Robert , Oduru Gloria , Kabuubi Nakawungu Prossy , Niwagaba Emmanuel , Abayo Elson , Kabagenyi Joyce , Zziwa Christopher , Tumusiime Josephine , Nakazibwe Esther , Kaweesa James , Muwonge Kakooza Fred , Akello Mirriam , Lubyayi Lawrence , Verweij Jaco , Nash Stephen , van Ree Ronald , Mpairwe Harriet , Tukahebwa Edridah , Webb Emily L , Elliott Alison M ,   LaVIISWA Trial Team, Sanya Richard , Nampijja Margaret , Mpairwe Harriet , O’Hara Geraldine , Nerima Barbara , Webb Emily , Spaans Remy Hoek , Muhangi Lawrence , Lubyayi Lawrence , Akurut Helen , Nalukenge Fatuma , Mirembe Beatrice , Okello Justin , Owilla Sebastian , Levin Jonathan , Nash Stephen , Namutebi Milly , Zziwa Christopher , Nakazibwe Esther , Tumusiime Josephine , Ninsiima Caroline , Amongi Susan , Kamukama Grace , Iwala Susan , Akello Florence , Akello Mirriam , Kizindo Robert , Sewankambo Moses , Nsubuga Denis , Cose Stephen , Wammes Linda , Nakawungu Prossy Kabuubi , Niwagaba Emmanuel , Oduru Gloria , Kabami Grace , Abayo Elson , Ssebagala Eric , Kakooza Fred Muwonge , Kabagenyi Joyce , Nkurunungi Gyaviira , Nalwoga Angela , Kizito Dennison , Tushabe John Vianney , Nassuuna Jacent , Verweij Jaco , Versteeg Serge , Ree Ronald van , Tumwesige Edward , Mpooya Simon , Abiriga David , Walusimbi Richard , Nannozi Victoria , Kabonesa Cynthia , Kaweesa James , Tukahebwa Edridah , Kizza Moses , Elliott Alison 
Published: September 2018

Background

The prevalence of allergy-related diseases is increasing in low-income countries. Parasitic helminths, common in these settings, may be protective. We hypothesized that intensive, community-wide, anthelminthic mass drug administration (MDA) would increase allergy-related diseases, while reducing helminth-related morbidity.

Methods

In an open, cluster-randomized trial (ISRCTN47196031), we randomized 26 high-schistosomiasis-transmission fishing villages in Lake Victoria, Uganda, in a 1:1 ratio to receive community-wide intensive (quarterly single-dose praziquantel plus albendazole daily for 3 days) or standard (annual praziquantel plus 6 monthly single-dose albendazole) MDA. Primary outcomes were recent wheezing, skin prick test positivity (SPT), and allergen-specific immunoglobulin E (asIgE) after 3 years of intervention. Secondary outcomes included helminths, haemoglobin, and hepatosplenomegaly.

Results

The outcome survey comprised 3350 individuals. Intensive MDA had no effect on wheezing (risk ratio [RR] 1.11, 95% confidence interval [CI] 0.64–1.93), SPT (RR 1.10, 95% CI 0.85–1.42), or asIgE (RR 0.96, 95% CI 0.82–1.12). Intensive MDA reduced Schistosoma mansoni infection intensity: the prevalence from Kato Katz examinations of single stool samples from each patient was 23% versus 39% (RR 0.70, 95% CI 0.55–0.88), but the urine circulating cathodic antigen test remained positive in 85% participants in both trial arms. Hookworm prevalence was 8% versus 11% (RR 0.55, 95% CI 0.31–1.00). There were no differences in anemia or hepatospenomegaly between trial arms.

Conclusions

Despite reductions in S. mansoni intensity and hookworm prevalence, intensive MDA had no effect on atopy, allergy-related diseases, or helminth-related pathology. This could be due to sustained low-intensity infections; thus, a causal link between helminths and allergy outcomes cannot be discounted. Intensive community-based MDA has a limited impact in high-schistosomiasis-transmission fishing communities, in the absence of other interventions.

Clinical Trials Registration

ISRCTN47196031.