This is another paper on Health Metrics of Helminths:

www.sciencedirect.com/science/article/pii/S0001706X13003501

I am not sure how much of the paper you'd be able to see if you are not registered for the journal, but it has a table showing various helminths.

The one for Ascaris says that
1,110,600 DALYs due to disability excl death
204,000 DALYs due to death
1,314,800 total

for all the helminths
13,676,700 DALYs due to disability excl death
608,000 DALYs due to death
14,284,200 total

in comparison malaria
4,070,000 due to disability excl death
78,615,000 due to death
82,685,200 total

So it seems that it doesn't cause a lot of death but significantly slows down a lot of people.

There is a lot of other information, we should get someone to explain to us what it all means

The conclusion says:

Health metrics are a commonly used system of estimating the impact of health care interventions in policy planning. While they serve a useful role in CEA, they are flawed in their estimation of the impact of diseases on individual and community well-being. While many decision-makers have assumed that the DALY is an accurate measure of the impact of parasitic diseases on global health, the limitations of the DALY system mean that major aspects of helminthic disease are overlooked in most burden assessments. More work is needed for long-term longitudinal assessment of the outcomes of helminth control, including outcomes specifically relevant to ‘disability’ as viewed by social planners and health economists. Health planners are not obliged to accept current DALY or QALY estimates as face value. If there is sufficient reason to believe that the disability from a given disease is greater than that used by the GBD2010, one may choose to ‘re-calibrate’ the disability weight and use the published GBD2010 prevalence and incidence numbers to recalculate ‘revised’ DALYs for any suite of competing conditions under consideration for control.

Also this brief note (I can't find a corresponding full paper) from here apha.confex.com/apha/142am/webprogram/Paper310874.html

Schistosomiasis and soil-transmitted helminthiasis: The 6-months results of a community-directed treatment intervention in Caxito, Angola

Schistosomiasis and soil-transmitted helminthiasis (STH) are major public health problems affecting 2 billion individuals, disproportionately at poor communities in low income countries. We aimed to study the 6-month impact on urinary schistosomiasis and STH of a generalized community treatment (single dose praziquantel and albendazole).

We examined children (2-15 years) from one hamlet, that provided urine and stool samples at baseline (n=198), 1 (n=106) and 6 (n=98) months; 61 children (33 school aged, 35 male) completed the protocol. At baseline, 43/61 (70.5%) children presented Schistosoma haematobium (75.8% in the baseline total sample) and 10 (16.4%) STH (30.5% in the initial sample, p=0.004). Of those infected with S. haematobium 36.1% presented heavy infection (≥500 eggs/10 ml of urine). The most frequent STH was Trichuris trichiura in 8.2%. However the most commonly found helminth was Hymenolepis nana-14.8%. One month after chemotherapy there was a significant (p=0.001) decrease in S. haematobium (from 43 to 29, but 5.6% of negative cases turned positive); at six months, the prevalence was similar to baseline, 77% for S. haematobium (78% in the global sample) but 8.2% for STH; No differences were found between preschool (2-5 yrs.) and school (6-15 yrs.) children. Considering the 61 children, median egg concentration was 630 at baseline, 60 at 1-month and 320 at 6-months, p<0.05.

Longitudinal studies are extremely complex in these settings, but we were able to show that Schistosomiasis and STH treatment presented low efficiency, reinfections occurred rapidly and standing alone anthelmintic therapy is an ineffective choice beyond immediate morbidity effects.

There are a couple of interesting papers which I do not think we have discussed on the forum before.

Control of soil-transmitted helminthiasis in Yunnan province, People's Republic of China: Experiences and lessons from a 5-year multi-intervention trial

This one looked at interventions including education, latrine building and medication.

An interesting finding was that although there was a rapid reduction in the helminths from the interventions, there was also a rapid reinfection

The discussion section of the paper says:

We found that the provision of sanitation coupled with regular health education and bi-annual administration of anthelminthic drugs resulted in higher A. lumbricoides prevalence and infection intensity reductions than 6-monthly chemotherapy alone. Annual MDA only showed a limited effect. Similar trends were observed with regard to T. trichiura, but changes were slower and less pronounced. After 5 years of interventions; the community prevalence was still around 30–60% in the study villages with no further declines in one of the villages in the second phase of the study.

Mathewos, Biniam, et al. "Current status of soil transmitted helminths and Schistosoma mansoni infection among children in two primary schools in North Gondar, Northwest Ethiopia: a cross sectional study." BMC research notes 7.1 (2014): 88.

From the discussion:

The high burden of STH and S. mansoni infection among school children of the study area may show that the children may be a potential source of infection and transmission for the diseases in the study area. Since it is well documented that these diseases are known to lower cognitive ability of students, low efficiency and productivity in their education endeavors may also be expected.


Other remarkable feature that has been shown from this study was high numbers of the children were infected with more than one type of worms. For example, one-tenth of the study participants were infected by both S. mansoni and A. lumbricoides. Such co-infections of S.mansoni and A. lumbricoides could be attributed to the co-endemicity of the two species and also poor sanitation in the study area. The finding of the present study was similar to study conducted in Cote d’Ivoire. Co-infection may affect nutritional status of the children because of the combined effect of the different parasites that can deprive the important nutrients of the children.