Oral Myiasis (Fly Larvae in the Mouth)

Oral myiasis is an infestation of the mouth by fly larvae, better known as maggots, which feed on living or dead tissue, body fluids or food [1]. It is uncommon [2]: an analysis of the English-language medical literature from 1990 to 2020 found 157 published cases [3]. Most of the people affected are medically or socially vulnerable, such as people with neurological or psychiatric disabilities, people with cancer and people living in poverty [2][3].

Treatment combines removal of the larvae, often after applying a substance that suffocates them, with surgical cleaning of the wound, antibiotics and, in many reports, the antiparasitic medicine ivermectin [3][2]. Case reports describe larvae destroying healthy tissue and causing serious bleeding [4], and a 2026 report describes a man who died after larvae moving toward his throat probably blocked his airway [5].

Table of Contents

  1. What Oral Myiasis Is
  2. The Flies Involved
  3. Who Is Affected
  4. Where in the Mouth It Occurs
  5. Signs and Symptoms
  6. How Oral Myiasis Is Diagnosed
  7. Treatment
  8. Ivermectin in Oral Myiasis
  9. Oral Myiasis in Children
  10. Myiasis in Cancer and Hospital Patients
  11. Complications and Warning Signs
  12. Prevention as Described in the Reviews
  13. Key Research Papers
  14. Connections
  15. Featured Videos

What Oral Myiasis Is

The word myiasis comes from the Greek word for fly. It means an infestation of a living person or animal by fly larvae, the worm-like stage that hatches from a fly’s egg. It is common in animals and can also occur in people, including in the mouth, when flies lay their eggs in the tissues [6]. The flies belong to the Diptera, the true flies, which have a single pair of wings. Their larvae feed on dead or living tissue, body fluids or food, and cause extensive tissue destruction [7].

Myiasis is more common in regions with a warm and humid climate [4]. A 2014 review calls oral myiasis “fly-blown disease” and notes that, although it is mainly found in the tropics and subtropics, it is also seen in Western countries because of globalization, immigration and global warming [8].

A 2010 report describes two ways flies reach the mouth: a person swallows fly eggs, or a fly lays its eggs directly on a damaged area, such as a toothless stretch of gum or the tissues around the teeth [9]. Larvae can reach their last stage within days. In a 2003 case, the roughly 40 larvae removed from a woman’s upper gums were all in their last stage, probably laid five to seven days earlier [10].

The Flies Involved

Many kinds of fly can cause oral myiasis. In most reports published since 2020 the larvae were not identified to the species level; when they were, they were the Old World screwworm, the housefly and a flesh fly [2].

Fly larvae are not the only parasites found in the mouth. A 2025 systematic review (a review that gathers published reports by a fixed, repeatable method) of 95 publications on infestations of the mouth found that the most common parasites were fly larvae and worms such as Gongylonema pulchrum and Dirofilaria [18].

Who Is Affected

Reviews of published cases name the same groups of people again and again:

In the 2021 analysis of 157 cases, 67.5% of patients were male, the average age was 41.9 years, and the countries with the most cases were India (41%) and Brazil (29.5%) [3]. A 2026 review of 14 studies published since 2020 found a slight male majority, patients from a five-month-old baby to a 91-year-old adult, and a neurological, psychiatric or cancer-related condition in most of them [2].

Where in the Mouth It Occurs

In the 2021 analysis, the gums (gingiva) were the most affected site, in 29% of cases, followed by the palate (the roof of the mouth) in 25% and the lip in 21% [3]. The 2026 review found the front of the upper jaw and the palate most often affected [2], as did a 2022 review of 68 cases in children [1].

Single reports also describe larvae on the gum ridge where a tooth had been pulled [6], in a man with a fixed bridge held by dental implants [24], in a sinus cavity [25], and through the gums, lower lip, tongue and soft palate [5].

Signs and Symptoms

A 2014 review lists the symptoms most often reported: pain, swelling, an itchy sensation and a feeling of something moving in the mouth [8]. Case reports add:

How Oral Myiasis Is Diagnosed

The diagnosis usually rests on seeing the larvae. For a 12-year-old boy, “the diagnosis was made on the presence of larvae” [20]; for six patients with facial injuries, it was made after larvae had been extracted [4]. Where myiasis is common, such as in Brazil, the diagnosis is usually quite clear, but it can be challenging for clinicians in other countries when a patient picked up the infestation elsewhere [6]. The authors of a 2021 report wrote that the diagnosis “requires a high index of suspicion”, meaning that the clinician has to think of it [16].

Identifying the fly

Larvae can be sent to a laboratory to identify the species [4]. For a five-month-old baby, the larvae were identified under the microscope and by comparing the sequence of one of their genes with known species. The authors note that similar species are easily confused by traditional identification, and describe this combination as an effective tool for rapid diagnosis [16]. The authors of a report on a debilitated older man called for removing and identifying the maggots as soon as possible, to prevent further tissue damage and bacterial infection [25]. Even so, in most reports published since 2020 the larvae were not identified to the species level [2].

Treatment

A 2023 report notes that no standard treatment protocol can be found in the medical literature [24], and the authors of the 2021 analysis called for one to be established so that treatments can be compared [3]. The 2026 review found treatment “consistently multimodal” [2], and a 2025 systematic review concluded that treatment could benefit from combining surgical removal with medicines [18].

Removing the larvae

The traditional treatment is removal of the larvae one by one, which a 2004 report describes as “painful, distressing, and embarrassing both to the patient and to the dentist” [26]. A 2014 review calls surgical cleaning of the infected tissue, with removal of the maggots, the treatment of choice in most cases [8]. One man had 601 larvae removed in all [27].

Substances applied to the larvae

The 2021 analysis lists “asphyxiating substances”, which suffocate the larvae, among the treatments used [3]. Substances applied in individual reports include turpentine oil, applied so the larvae could be removed by hand [7] or used as a wound dressing [28]; ether on a soaked pad [24]; gentian violet, a purple antiseptic dye [21]; and a 10% phenol preparation (creolin) [4]. In two patients with screwworm larvae, flushing the wounds with the antibacterial nitrofurazone for three days left the maggots in a liquid-filled environment without oxygen. No surgery was needed, both healed uneventfully, and no adverse reactions were seen over two months of follow-up [9].

Surgical cleaning, antibiotics and medicines

Dead tissue is cut away and the wound cleaned, a step called surgical debridement, and most combined treatments include antibiotics [3][2]. After the larvae were cleared, some patients were referred to plastic surgery to repair the damage [21][29]. Antiparasitic medicines, mainly ivermectin, are the other common addition [2]. A 2018 review of 35 cases in older adults found that the preferred treatments were debridement alone or debridement combined with ivermectin [22].

Ivermectin in Oral Myiasis

Ivermectin is an antiparasitic medicine. A 2021 review describes oral ivermectin as “a safe broad spectrum anthelminthic” (a medicine against parasitic worms) and lists the conditions it had been given for in young children, including scabies, lice, worm infections and myiasis [30]. In oral myiasis it has been given by mouth, by injection under the skin and directly on the infested tissue. The reports are case reports, case series and small observational studies, and in most of them ivermectin was one part of a combined treatment [2].

By mouth

By mouth and on the tissue: the 2023 crushed-tablet case

An 82-year-old man with a fixed bridge held by dental implants had lesions extending through the space between his cheeks and gums and along the gum ridges on both sides of his upper jaw, and over a large part of his palate, with many larvae. He was first given a single 6 mg dose of ivermectin by mouth and a pad soaked in ether, and the larvae were then surgically removed and the wound cleaned. A crushed 6 mg ivermectin tablet was next applied directly to the tissue for two days, the remaining larvae were again removed, and he received antibiotics through a drip. The authors concluded that ivermectin by mouth and on the tissue, combined with antibiotics and debridement, “proved to be effective” [24].

By injection: six patients after facial injuries

In 2011, doctors reported six patients whose mouths had become infested with New World screwworm larvae after injuries to the face and skull. Treatment consisted of ivermectin injected under the skin (subcutaneously) and a 10% phenol preparation (creolin) applied locally to control the larvae. After 12 days in hospital (give or take one day), no larvae remained in the patients’ mouths and all six were discharged. Healing was uneventful, and no unwanted reactions were seen during treatment. The authors wrote that although the usual treatment is surgical removal of the maggots, drug treatments are “emerging as effective alternatives” [4].

Other reports with ivermectin

These published summaries name ivermectin without saying how it was given:

In cancer wounds

A 2025 prospective observational study followed 10 patients with advanced head and neck cancer who had maggots in a wound, the scalp, the mouth or a nostril. All were given albendazole (400 mg once a day), ivermectin 12 mg tablets, two antibiotics (amoxicillin with clavulanate, and metronidazole) and turpentine-oil dressings three times a day, for five days. Wound scores and related symptoms improved significantly on days 1, 3, 5 and 7, except bleeding, swelling, nausea, anxiety, loss of appetite and sense of well-being, which were unchanged on day 1 and improved afterwards. Side effects were self-limiting, and the authors noted that more comprehensive studies are required [28].

A 2026 review highlights a “triple therapy” of oral ivermectin, albendazole and the antibiotic clindamycin. It cites a single-centre prospective cohort that reported a reduction of more than 90% in the number of larvae by day 3, together with better pain and odour control [12].

Oral Myiasis in Children

A 2022 systematic review found 68 cases of oral myiasis in children aged 2 to 16, reported in 32 studies. Most involved the gums at the front of the upper jaw and the palate. The review describes cases in children as scarce but debilitating [1]. The 12-year-old boy with cerebral palsy is described in the ivermectin section above. Other reports:

Ivermectin in young children

At the time of a 2021 review, ivermectin was contraindicated (formally listed as not to be given) in children weighing less than 15 kilograms (about 33 pounds). The review gathered 1,088 such children who had been given ivermectin by mouth, for conditions including scabies, myiasis and worm infections. In all, 1.4% (15 of 1,088) had 18 adverse events, all mild and self-limiting, and no serious adverse events were reported. The authors concluded that the limited existing data suggest oral ivermectin is safe in these children, and that data from well-designed clinical trials are needed for further assurance [30].

Myiasis in Cancer and Hospital Patients

Cancers of the head and neck

A 2026 review describes myiasis in cancer wounds as a neglected but deeply distressing complication of advanced cancer, particularly of the head and neck. Head and neck cancer is especially common in low- and middle-income countries such as India, where patients often come for care late, when the cancer has already formed a large, open wound. These wounds, together with poverty, poor hygiene and physical weakness, give screwworm flies a fertile environment, and the infestation brings severe pain, a persistent smell, rapid wearing away of tissue and great psychological distress [12].

A 2022 scoping review (a broad survey of what has been published) found 56 patients with head and neck cancer and myiasis in 38 articles. Most were men (66%), the average age was 66.63 years, and most had squamous cell or basal cell cancers. The eyes, scalp, ears and mouth were the sites most often affected, and the larva most often reported was a Chrysomya species (13%). The authors wrote that the infestation can speed up the cancer’s progress and make it more deadly through local or bodywide complications [23].

Hospital-acquired myiasis

Myiasis that begins after a patient is admitted to hospital is called nosocomial, or hospital-acquired, myiasis, and it is rare [14]. A 2026 report described an 89-year-old woman in hospital in northeastern Iran with oral myiasis from the Old World screwworm. The authors found that most hospital-acquired cases in Iran involved the throat and nose and occurred mainly in intensive care patients [14]. The authors of the report on the 13-year-old boy in intensive care describe preventing hospital-acquired myiasis as an essential part of every hospital’s infection-control programme [17], and the 2026 structured review notes that oral myiasis can be life-threatening in critically ill patients [2].

Complications and Warning Signs

Many reported cases ended well. The 2018 review found a good prognosis of cure in older adults when there were no systemic complications [22], and in the 2003 periodontitis case the gum tissues were healing normally one week after the larvae were removed [10].

Signs described in the most severe cases

The most severe and fatal cases featured difficulty breathing, a bluish tinge to the skin, reduced consciousness, larvae spreading toward the throat and bleeding from the mouth [5][4]; larvae burrowing into the palate [13] or involving a sinus [25]; and malnutrition, dehydration and extreme weakness [27].

Prevention as Described in the Reviews

The reviews and case reports describe prevention in terms of flies, hygiene and care for people who cannot look after themselves:

Key Research Papers

  1. Jain A, Taneja S. Oral myiasis affecting paediatric patients: a systematic review. J Stomatol Oral Maxillofac Surg. 2022;123(3):e32-e36. PubMed PMID: 34260982
  2. Monsalves N, Estrada F, Venegas J. Oral Myiasis: A Structured Review of Risk Factors, Clinical Presentation, and Treatment. Cureus. 2026;18(9):e116137. PubMed PMID: 42733919
  3. Dos Passos JBS, Coelho LV, de Arruda JAA, Silva LVO, do Valle IB, Santos MS, et al. Oral myiasis: Analysis of cases reported in the English literature from 1990 to 2020. Spec Care Dentist. 2021;41(1):20-31. PubMed PMID: 33125723
  4. Duque FL, Ardila CM. Oral myiasis caused by the screwworm Cochliomyia hominivorax treated with subcutaneous ivermectin and creolin: report of six cases after trauma. Dent Traumatol. 2011;27(5):404-7. PubMed PMID: 21535400
  5. Calvopiña M, Jordan-Guarnizo E, Galeas C, Rodriguez-Hidalgo R. Severe Oral Myiasis in an Elderly Man with Epilepsy Caused by the New World Screwworm (Cochliomyia hominivorax) in Subtropical Ecuador. Am J Trop Med Hyg. 2026;114(6):1180-1183. PubMed PMID: 41980547
  6. Rauen CA, Lança ML, Jitumori C, Inaoka S, Bonan P, Kaminagakura E. Oral myiasis in humans. Clin Exp Dermatol. 2022;47(4):739-742. PubMed PMID: 34716999
  7. Zachariah JE, Sehgal K, Dixit UB, Bhatia R. Oral myiasis: a case report. Spec Care Dentist. 2014;34(1):51-3. PubMed PMID: 24382372
  8. Hassona Y, Scully C, Aguida M, de Almeida OP. Flies and the mouth. J Investig Clin Dent. 2014;5(2):98-103. PubMed PMID: 24574273
  9. Lima Júnior SM, Asprino L, Prado AP, Moreira RW, de Moraes M. Oral myiasis caused by Cochliomyia hominivorax treated nonsurgically with nitrofurazone: report of 2 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010;109(3):e70-3. PubMed PMID: 20219589
  10. Gomez RS, Perdigão PF, Pimenta FJ, Rios Leite AC, Tanos de Lacerda JC, Custódio Neto AL. Oral myiasis by screwworm Cochliomyia hominivorax. Br J Oral Maxillofac Surg. 2003;41(2):115-6. PubMed PMID: 12694705
  11. de Souza Barbosa T, Salvitti Sá Rocha RA, Guirado CG, Rocha FJ, Duarte Gavião MB. Oral infection by Diptera larvae in children: a case report. Int J Dermatol. 2008;47(7):696-9. PubMed PMID: 18613876
  12. Gupta AK. Management of myiasis in advanced head and neck cancers: a comprehensive review. Support Care Cancer. 2026;34(6). PubMed PMID: 42133099
  13. Kumar GV, Sowmya G, Shivananda S. Chrysomya bezziana oral myiasis. J Glob Infect Dis. 2011;3(4):393-5. PubMed PMID: 22224006
  14. Mirbadie SR, Mohaghegh MA, Skandary F, Soleymani E, Nikbin F, Sazmand A. Nosocomial oral myiasis caused by Chrysomya bezziana in Iran: A new case and review of human myiasis in the country. IDCases. 2026;43:e02497. PubMed PMID: 41631118
  15. Abosdera MM, Morsy TA. Oral cavity myiasis in children: first demonstration in Egypt with general review. J Egypt Soc Parasitol. 2013;43(3):737-46. PubMed PMID: 24640873
  16. Zhou M, Cao K, Huang H, Luo X, Wang Y, Ma W, et al. Neonatal oral myiasis caused by the larvae of Sarcophaga ruficornis (Diptera: Sarcophagidae): a case report. BMC Infect Dis. 2021;21(1):1067. PubMed PMID: 34654380
  17. Martínez-Rojano H, Huerta H, Hernández-Triana LM, Ruiz Pérez EF, Sámano R. Nosocomial Myiasis Caused by Lucilia sericata (Diptera: Calliphoridae) in a Pediatric Patient in Mexico. Case Rep Infect Dis. 2020;2020:1285459. PubMed PMID: 32082658
  18. Lorusso F, Alla I, Tari SR, Gehrke SA, Scarano A. Oral cavity myiasis and mouth parasitic infestations: A systematic review. J Stomatol Oral Maxillofac Surg. 2025;126(5S):102425. PubMed PMID: 40505774
  19. Novo-Neto JP, Dos Santos Fde S, Pontes AE, Ribeiro FS, Scannavino FL, Martins AT. Oral Myiasis Caused by Cochliomyia hominivorax in a Disabled Person. Case Rep Pathol. 2015;2015:904658. PubMed PMID: 26266071
  20. Vasanthakumar V, Varalakshmi PR, Vanmathi R. Oral Myiasis of Maxilla (Palatal Gingiva). Contemp Clin Dent. 2020;11(2):162-164. PubMed PMID: 33110330
  21. Abdo EN, Sette-Dias AC, Comunian CR, Dutra CE, Aguiar EG. Oral myiasis: a case report. Med Oral Patol Oral Cir Bucal. 2006;11(2):E130-1. PubMed PMID: 16505789
  22. Filho AO, Dias D, Miranda Á, Hebling E. Oral myiasis in older adult with severe Alzheimer's disease. Spec Care Dentist. 2018;38(2):99-106. PubMed PMID: 29505667
  23. Gonçalves KKN, de Araújo ESM, Barbirato DS, do Lago CAP, do Egito Vasconcelos BC. Head and neck cancer associated with myiasis. Int J Oral Maxillofac Surg. 2022;51(7):847-853. PubMed PMID: 34602319
  24. Sangalette BS, Bortoloto JGP, Pavoni RF, Cappellari VI, Capelari MM, Shinohara AL, et al. Treatment of oral myiasis in a patient with implant-supported fixed prosthesis. Rev Inst Med Trop Sao Paulo. 2023;65:e27. PubMed PMID: 37075334
  25. Ribeiro MC, Pepato Ade O, De Matos FP, Sverzut CE, Abrahão AA, Trivellato AE. Oral myiasis in an elderly patient. Gerodontology. 2012;29(2):e1136-9. PubMed PMID: 21029155
  26. Shinohara EH, Martini MZ, de Oliveira Neto HG, Takahashi A. Oral myiasis treated with ivermectin: case report. Braz Dent J. 2004;15(1):79-81. PubMed PMID: 15322651
  27. Laureano Filho JR, Bezerra TP, Lima FT, Campelo RI. Extensive oral lesion colonized with 601 myiasis larvae. Trop Doct. 2011;41(1):61-2. PubMed PMID: 21109606
  28. Mishra V, Saifi AM, Mitra P, Agarwal A, Meharchandani M. Management of Malignant Wound Myiasis in Advanced Head‑and‑Neck Cancer Patients: A Prospective Observational Study. Indian J Otolaryngol Head Neck Surg. 2025;77(3):1449-1453. PubMed PMID: 40093442
  29. Khan HZ, Shahid SA, Bakht N, Zaidi SSN. Myiasis Encountered in Squamous Cell Carcinoma of the Oral Cavity: A Case Report. Cureus. 2024;16(6):e62414. PubMed PMID: 39011201
  30. Jittamala P, Monteiro W, Smit MR, Pedrique B, Specht S, Chaccour CJ, et al. A systematic review and an individual patient data meta-analysis of ivermectin use in children weighing less than fifteen kilograms: Is it time to reconsider the current contraindication? PLoS Negl Trop Dis. 2021;15(3):e0009144. PubMed PMID: 33730099

PubMed Topic Searches

  1. PubMed: Oral myiasis
  2. PubMed: Ivermectin and oral myiasis
  3. PubMed: New World screwworm myiasis
  4. PubMed: Old World screwworm myiasis
  5. PubMed: Hospital-acquired (nosocomial) myiasis
  6. PubMed: Myiasis in head and neck cancer

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