Intestinal helminths in dogs and cats on the Antillian Islands Aruba, Curaçao and Bonaire

An investigation into the prevalence, identity and size of population of intestinal helminths in dogs and cats was carried out in the Dutch Antillian Islands, Curaçao, Bonaire and Aruba during April and May 1974. Ninety-one dogs and 83 cats were examined. In all, 4,824 helminths were isolated and identified. The following species were isolated from dogs: Dipylidium caninum (most frequent), Ancylostoma caninum (frequent in Curaçao), Toxocara, Taenia hydatigena and Ancylostoma braziliense. Species isolated from cats: Dipylidium caninum (most frequent) Ancylostoma tubaeforme (frequent in Curaçao), Oncicola canis, Taenia taeniaformis, Spirometra (mansonoides), Platynosomum (fastosum), Toxocara, Trichuris and Thelazia. The man-infecting hookworm species Ancylostoma ceylanicum was not found at all and A. braziliense was only found in dogs in Aruba in light infections. Remarkable differences in the prevalence of parasitic infections were demonstrated between Curaçao and the two other islands Aruba and Bonaire, especially regarding the frequency and worm burden of the hookworms. It was suspected that this was due to the recent increase in the number of dogs in Curaçao.

Pulmonary ascariasis in tropical communities

To determine the incidence of Loeffler's syndrome in a tropical region, a survey was conducted over a 1-year period in two locations in Colombia, South America, one inland and urban (Cali), the other rural and coastal (Guapi). Among 700 hospitalized patients, 12,000 patients coming to health centers, and 44 families with 328 members, 4 cases of Loeffler's syndrome were found--3 during the survey and 1 before it began. Only one was typical and of some severity. None of the family members developed a perceptible reaction to larvae, though surveillance was close and 83 new intestinal infections were documented. Infection rates for intestinal ascariasis were 25% to 30% in Cali, and 80% to 90% in Guapi. When infections in 30 families were eliminated, previous levels of infection were reached within 10 months. When undisturbed by treatment, the levels of intestinal infection remained stable or showed fluctuations which were not linked to climatic changes. In view of the high prevalence of infection and year-round transmission, which was assumed to occur frequently in the population, it is noteworthy that symptomatic pulmonary ascariasis appeared to be rare and complications from adult worms in heavy infections were uncommon. The findings suggest that frequent and uninterrupted contact between Ascaris lumbricoides and its host results in a high degree of natural tolerance and control.

[The intestinal parasite fauna in patients, returned from the tropics, from the Dresden district]

It is reported on the affection with intestinal parasites in 438 persons who returned from the tropics. In these test persons were also established only those species of parasites which were proved in the Dresden inhabitants. However, there were remarkable quantitative differences between the affection of the persons returning from the tropics and the Dresden inhabitants. Thus by laboratory examinations in Dresden in the persons returning from the tropics were established infections with Entamoeba histolytica (7.0%), with Dientamoeba fragilis (17.9%), with Lamblia intestinalis (9.0%) as well as with Trichuris trichiura (3.4%), where as the extensity of affection with the corresponding parasites is for the Dresden inhabitants 1.9%, 4.7%, 5.0%, and 1.6%. It is referred to the fact that all persons who returned from the tropics should parasitologically be examined for an infection with Entamoeba histolytica.

[Infestation with intestinal helminths in the inhabitants of the city of Dresden]

It is reported on the data of helminthological investigations performed on 1323 Dresden inhabitants at the age of 14 to 70 years. Furthermore the notifications of the affections with tapeworm which had come into the district hygiene inspection of Dresden were evaluated. An affection with Ascaris lumbricoides of 1.2%, with Trichuris trichiura of 1.6%, with Enterobius vermicularis of 14.5% and with Taeniarhynchus saginatus of about 1% were proved. In the case of Enterobius vermicularis the for the most part affected age groups were the 14- to 20-year-old test persons and concerning Taeniarhynchus saginatus the 21- to 70-year-old test persons. Accumulations of the extensity of the affection with helminths bound to a species of hosts were not detected. Concerning the taeniarhynchosis since 1966 a permanent increase of the extensity of affection is to be registered. The duty of notification concerning taeniarhynchosis is often neglected. Only about 1/6 of the affection with tapeworm is notified in the district hygiene inspection.

A comparison of post-mortem analysis of helminths with faecal egg counts

Intestinal helminth infections are very common amongst residents of the Colombo area. Most common by post-mortem examination of 104 cases of sudden death were Trichuris trichiura (97.1%), Necator americanus (88.5%), Enterobius vermicularis (77.9%) and Ascaris lumbricoides (40.4%). Trematode and cestode infections were not encountered except a single case of H. diminuta infection. A comparison of the results obtained by the direct smear method for examining stools missed cases harbouring gravid females of up to 3 Ascaris lumbricoides, 29 Trichuris trichiura and 66 Necator americanus. The direct smear revealed all the helminths present except threadworms in only 30% of the cases. The correlation between worm loads calculated from ova counts and actual numbers harboured was fairly close in 19 out of 35 cases for Ascaris and 37 out of 78 cases for Necator americanus. Highly erroneous results were obtained in many instances when worm loads were calculated from the results of ova counts.

A rapid technique for the concentration and collection of helminth eggs from large quantities of faeces

A simple semi-mechanical sieving apparatus is described which rapidly concentrates helminth eggs from relatively large volumes of faeces. Tests showed the percentage recoveries of N. battus eggs after sieving 500, 750 and 1000 ml of diluted ovine faeces were 94·1, 88·1 and 84·8 respectively; for T. suis, Oesophagostomum spp. and H. rubidus eggs from 1000 ml. of porcine faeces, the percentage recovery was 94·8 for T. suis and 94·7 for the latter two worms. T. trichuira eggs have also been separated from human faeces using this apparatus.