The Humanitarian Health Evidence Review

Of the current list of 17 diseases currently classified as NTDs by the WHO, four – lymphatic filariasis (‘elephantiasis’), oncocerchiasis (‘river blindness’), guinea worm, and trachoma – have active global elimination programmes underway with the aim of elimination by 2020. An additional two NTDs – schistosomiasis and soil transmitted/intestinal helminthes (STHs) – have active control programmes underway with increasingly narrowing targets towards elimination in the near future.

• Of over 60 papers initially retrieved, the vast majority of research focused on infection or disease prevalence (usually via a one-time cross sectional survey) without any information on an intervention conducted.
• This review found nine research articles that evaluated the success of NTD interventions in humanitarian settings
• The interventions against NTDs included in this review include those against leishmaniasis (N=5), schistosomiasis (N=3), and trachoma (N=1).
• Five papers included an NTD evaluation with a refugee population in a host or originating country before being followed up in the United States; all five of these studies were on STHs.
• Of the 17 diseases currently classified as NTDs, only four were included in this review.
• Despite the fact that they are due for elimination by 2020, this review did not retrieve any intervention studies against lymphatic filariasis, onchocerciasis, or guinea worm and only one study on trachoma in these populations.

Leishmaniasis (Visceral):

• All five leishmaniasis intervention studies were against visceral leishmaniasis (VL).
• The one study graded as high quality demonstrated that VL treatment is amongst the most cost effective public health inteventions available (Griekspoor 1999). It is markedly more cost-effective, at USD $18 saved / DALY averted than interventions in the USD$20-25/DALY range such as measles, polio, or DPT vaccine.
• Three of these studies were graded medium and 1 low quality; none provided tests of statistical association or strength of magnitude of evidence in relation to VL treatment.
• All VL interventions included in this review occurred in Africa, and all with refugee populations who fled as a result of armed conflict. All studies evaluated treatement with sodium stibobluconate of varying dosages/regimens.
• Of these five studies, three were conducted 13-18 years ago (Boussery 2001, Griekspoor 1999, Seaman 1996) and two were conducted 23 years ago (Zijlstra 1991, De Beer 1991).
• The high quality economic study demonstrated that VL treatment is amongst the most cost-effective public health interventions. The medium and low quality, old studies conclude that sodium stibogluconate is safe and effective treatment for VL.

Schistosomiasis:

• Of the three schistosomiasis interventions included, two were against S. japonica, and one was against S. mekongi.
• All of the schistosomiasis intervention studies were graded as low quality; none provided tests of statistical association or strength of magnitude of evidence.
• All schistosomiasis interventions included here occurred in Asia, two as the result of floods, one in population displaced by armed conflict.
• Two studies evaluated praziquantel and one study artemeter treatment.
• Of the three studies, two were conducted 15 years ago (Huang 1998, Song 1997) and one is 30 years old (Keittivuti 1984).
• These low quality, old studies conclude that praziquantel and artemeter are both effective at reducing parasite burden.

Trachoma:

• Only one intervention was found against trachoma (Javaloy 2003).
• This study was graded to be of medium quality; no tests of statistical association or strength of magnitude of evidence were conducted.
• This study from Africa, conducted in children who moved as a result of armed conflict, evaluated single-dose azithromycin and found it to be effective in clearing Chlamydia trachomatis infection via sequential PCR screening and testing.

Soil transmitted/intestinal helminthes (STHs):

• Five studies included interventions against STHs, but they are included as a separate category because while the intervention was conducted in the host/originating country, the follow-up was conducted in a high income country.
• Of these five studies, all were graded high quality and two included statistical tests of association and strength of magnitude of evidence (Goswami 2009, Shah 2008).
• One economic analysis of the pre-departure albendazole regimen concluded the programme was highly effective at reducing morbidity and mortality, as well as cost-saving (Muennig 1999).