As we discussed earlier in another post, some parasites can be infected with viruses. However, viruses are the smallest particles able to infect living organisms and are really widespread in all living organisms. It is then not surprising to find them within parasites. This discovery leads us to wonder if parasite can also be infected with another parasite.
The actual answer to this question is that there is not enough research or evidence to back up this idea. Thus far, there has not been any claims of any parasite being a host for another parasite. Additionally, there is currently no evidence of parasite being infected by another parasite in scientific literature databases. However, in science, just because something has not been proven or observed yet doesn’t mean it isn’t possible. In fact, according to me, it is still possible that a parasite could be infected by another specific parasite.
Research efforts in the area of parasitology are in fact quite limited to species infecting humans and/or animals. Because there is no mention of such thing in the current scientific literature, it is quite likely that parasite species of medical and veterinary significance cannot usually be infected by another parasite or that it is extremely rare. Parasites are quite big microorganisms and I sincerely think that it would have already been discovered if a parasite involved in human or animal health where able to be a host for another parasite. However, there are a lot more non-pathogenic parasites than pathogenic ones. As such, it is estimated that thousands of parasite species are free-living organisms living by themselves in the environment, meaning that they do not need to infect a host in order to fulfill their life cycle. These parasites are not very well studied by researchers because of their lack of relevance in human or animal medicine. Consequently, many parasite species are not studied and a lot of them have even not been discovered yet. As a matter of fact, these non-studied or non-discovered parasites could possibly be infected with another parasite without anybody knowing it.
In fact, as parasites are quite big, especially helminths that are considered to be some kind of small animals, it is quite possible for them to be infected with a smaller organism. As such, it could be likely to find one day somewhere in nature a helminth able to be infected by a smaller parasite, such as a protozoan parasite. We will have to wait and see!