First report of external ophthalmomyiasis caused by Lucilia sericata Meigen in a healthy patient without predisposing risk factors

Ophthalmomyiasis Externa and Importance of Risk Factors, Clinical Manifestations, and Diagnosis: Review of the Medical Literature

OBJECTIVE

This review aims to describe and compare the risk factors, clinical course, diagnosis, and parasitologic features of external ophthalmomyiasis. We also discuss the different preventive measures and the effect of global warming in a large case series reported from January 2000 to December 2022.

METHODS

We perform a literature review of reported cases of external ophthalmomyiasis to determine the clinical characteristics, therapeutic management, and information on the organisms that most commonly cause external ophthalmomyiasis.

RESULTS

A total of 312 cases of external ophthalmomyiasis were recorded. The most common causative organism was Oestrus ovis (Linnaeus) (Diptera: Oestridae), accounting for 72.1% of cases, followed by Dermatobia hominis (Linnaeus Jr. in Pallas, 1781) (Diptera: Oestridae) at 5.4%, Lucilia sericata (Meigen) (Diptera: Calliphoridae) at 0.96%, and Chrysomyia bezziana (Villeneuve) (Diptera: Calliphoridae) at 0.96%. Before experiencing symptoms, 43.6% of cases reported having direct contact with flies or being hit in the eye, 33% reported no associated risk factors, 9.3% reported living with sheep and goats, and 7.7% reported a history of foreign objects entering the eye. The most common symptoms for those affected by O. ovis were sudden onset, including a foreign body sensation and movement, redness, tearing, itching, swelling, irritation, photophobia, burning, and ocular secretion. In cases caused by D. hominis, symptoms included eyelid edema, pain, redness, itching, movement within the lesion, ocular irritation, and discharge. Regarding occupational or recreational activity, agriculture, and livestock had the highest incidence, followed by trades and technical activities, being a student, and having traveled to an endemic region for work or recreation.

CONCLUSION

Patients with red eyes may suffer from external ophthalmomyiasis, which requires a thorough examination to diagnose and treat it early. Moreover, as the temperature increases due to climate change, it is essential to consider how this will affect the spread of different pathogens.

A case of facultative ophthalmomyiasis externa due to Calliphoridae and review of the literature

Purpose

To describe a case of bilateral facultative ophthalmomyiasis externa due to Calliphoridae in a 30-year-old male assault victim at a suburban hospital in New York and review the relevant literature.

Observations

An adult male was found to have maggot infestation of both eyes and severe secondary injury to the left cornea and ocular surface. He was treated with manual larvae removal, oral ivermectin, broad spectrum IV antibiotics, and topical antibiotics. Anterior segment reconstruction was required.

Conclusions and importance

We report the first case of ophthalmomyiasis due to Calliphoridae in the United States and document the vision threatening potential of this rare condition. Timely examination by an ophthalmologist with early debridement may help prevent vision-threatening sequelae.

A case of ophthalmomyiasis interna in the Pacific Northwest

PURPOSE

We report a case of ophthalmomyiasis interna successfully removed in toto with pars plana vitrectomy.

OBSERVATIONS

An 84-year-old woman with recent close contact with lambs presented with a new floater. Examination revealed subretinal tracks pathognomonic for ophthalmomyiasis and a larva suspended in the vitreous. The larva was successfully removed in toto with pars plana vitrectomy by aspiration through the vitreous cutter.

CONCLUSIONS AND IMPORTANCE

Aspiration with pars plana vitrectomy can be considered a primary therapeutic modality for botfly larvae suspended in the vitreous. In our case, in toto removal of the larvae reduced the risk of inflammatory reaction.

A Case of Insect Colonization Before the Death

Forensic entomology is a branch of forensic science in which insects are used as evidence in legal investigations relating to humans, domestic animals and wildlife. One of the theoretical pillars on which the discipline is based concerns the fact that flies colonize a body after death. However in cases of myiasis, maggots are present before death, with consequences in the correct estimation of the minimum postmortem interval (mPMI). We report here the case of a woman, largely colonized by fly larvae, who has lain alive in her garden for four days prior to being rescued. Larvae were found on the conjunctivae, the bronchi, the rectum and vagina. The woman's death, two months later, was caused by tetanus. The consequences of myiasis on mPMI estimation are here discussed. In fact, despite she was still alive larvae, indicated and estimated age of 1.5-2.5 days, based on environmental and body temperature.

Update on pathology of ocular parasitic disease

Parasites are a group of eukaryotic organisms that may be free-living or form a symbiotic or parasitic relationship with the hosts. Consisting of over 800,000 recognized species, parasites may be unicellular (Protozoa) or multicellular (helminths and arthropods). The association of parasites with human population started long before the emergence of civilization. Parasitic zoonotic diseases are prevalent worldwide including India. Appropriate epidemiological data are lacking on existing zoonotic parasitic diseases, and newer diseases are emerging in our scenario. Systemic diseases such as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. Acquired Toxoplasma infections are rising in immune-deficient individuals. Amongst the ocular parasitic diseases, various protozoas such as Cystoidea, trematodes, tissue flagellates, sporozoas etc. affect humans in general and eyes in particular, in different parts of the world. These zoonoses seem to be a real health related problem globally. Recent intensification of research throughout the world has led to specialization in biological fields, creating a conducive situation for researchers interested in this subject. The basics of parasitology lie in morphology, pathology, and with recent updates in molecular parasitology, the scope has extended further. The current review is to address the recent update in ophthalmic parasites with special reference to pathology and give a glimpse of further research in this field.

Incidence of myiasis among humans-a review

Myiasis, the infestation of tissues of live humans and other vertebrate animals with dipteran larvae (maggots), is a phenomenon of widespread occurrence throughout the tropical regions of the world. It is commonly seen in domestic and wild animals but occurs rarely in man also. The tissue invasion in man by maggots is generally a well-recognized complication of neglected wounds. The condition may be asymptomatic but occasionally results in more or less severe problems and even death when larvae invade body cavities or areas that forbid their direct visual examination. Many cases of myiasis, however, usually do not reach the attention of medical practitioners because of the tendency of the mature larvae to migrate out of the lesion for pupation. In the present study, the authors reviewed the past literature describing the cases of human myiasis, causative fly species and predisposing factors for the onset of the same. The aim of the present manuscript is to provide a database for the future reference of medical entomologists, medical practitioners and veterinarians. Review of literature revealed that 37 fly species belonging to ten families were responsible worldwide for the onset of human myiasis. The incidence of myiasis among humans can be correlated to increasing fly populations, poor hygienic conditions and presence of domestic animals in the close vicinity. Other factors responsible for myiasis include neglected open wounds and foul-smelling discharge from natural body openings. Moreover, ignorance plays a key role in its occurrence since people are generally unaware about the actual cause and often correlate the condition to their superstitious beliefs. It is emphasized that the patients should not neglect their wounds and should take proper medical care; otherwise, myiasis may supervene.