In short: New World screwworm (gusano barrenador, Cochliomyia hominivorax) is present in Guatemala. MAGA confirmed the first case in a calf in Izabal on 29 October 2024 and, by its 2 September 2026 count, found 5,169 positive animals among 661,577 inspected between October 2024 and August 2026. MAGA has also reported cases in dogs, most recently in a post dated 3 September 2026. USDA APHIS lists Guatemala as “not free” of screwworm, so a dog flying to the US needs a certificate from an official government veterinarian that it was inspected within 5 days before shipment. For people, CDC reports more than 2,600 human cases across Central America and Mexico and publishes a short prevention list, quoted below. This page reports what those agencies publish; it is not medical or veterinary advice.
What the agencies say, in one table
| Question | Published answer | Source |
|---|---|---|
| First confirmed case in Guatemala | A calf in Izabal, 29 October 2024 | MAGA, 29 Nov 2024 |
| Animals inspected, Oct 2024 to Aug 2026 | 661,577 | MAGA, 2 Sep 2026 |
| Animals positive, same period | 5,169 | MAGA, 2 Sep 2026 |
| Animals given preventive or curative wound treatment | 254,848 | MAGA, 2 Sep 2026 |
| Reports received and attended | 4,282 | MAGA, 2 Sep 2026 |
| Vehicles inspected for animal movement | 26,981 | MAGA, 2 Sep 2026 |
| Guatemala’s screwworm status for US dog imports | “not free” | APHIS table, last modified 21 Jan 2026 |
| Cases in Central America and Mexico | More than 209,400 in animals, more than 2,600 in people | CDC, 11 Aug 2026 |
| US risk to the public | “very low” | CDC, 11 Aug 2026 |
MAGA’s September 2026 count is national and does not break down by species or department. The MAGA posts we read do not give a count of human cases in Guatemala; CDC’s human figure covers Central America and Mexico together.
How it arrived and what Guatemala is doing
CDC’s account: in 2023, Panama and Costa Rica identified an outbreak, and since then all countries in Central America and Mexico, where NWS was previously controlled, have identified cases in animals (livestock, pets and wildlife) and in people.
In Guatemala, MAGA’s one-month report (29 November 2024) counted 28 cases, 27 in Izabal and 1 in Petén, and said more than 20 million sterile flies had been released by overflight. MAGA’s May 2025 post dates the Estado de Emergencia de Sanidad Animal to 29 October 2024. Its September 2026 report adds a pilot fly-trapping plan, 30,457 people linked to livestock activities trained, and work with the Ministerio de Salud Pública y Asistencia Social (MSPAS), municipalities and academia under a “One Health” approach.
Training has reached health workers: on 21 September 2026, 30 staff of the Centro de Salud of Santa Catarina Barahona, Sacatepéquez were trained to recognise cases and act on suspicions, with OIRSA support; a separate virtual session trained 184 professionals and technicians in epidemiological surveillance, taught by Mexico’s SENASICA (MAGA, 4 September 2026).
Dogs and cats in Guatemala
Pets are not a side note in MAGA’s reporting.
- 3 September 2026: MAGA attended possible dog cases in four departments. A 13-year-old Golden Retriever in zona 11, Guatemala City had larvae in a wound on the knee joint and was treated; a dog in Samayac, Suchitepéquez had its larvae extracted and was treated; a feral dog in Retalhuleu received preventive treatment. A dog checked in Mixco had no larvae, and one in San Pedro Carchá, Alta Verapaz had no active larvae; in Mixco, abundant flies around the house led to insect-control advice.
- 28 May 2025: of 97 new cases reported up to 23 May 2025, 23 were dogs and 2 were cats. MAGA wrote that screwworm affects all warm-blooded animals, “incluidos los humanos”.
MAGA’s published advice for pet owners (May 2025): check pets regularly for wounds or skin infections, paying special attention to the ears, mucous membranes, abdomen and between the toes; take a wounded pet to your trusted veterinarian; keep the skin healthy and free of external parasites.
Where MAGA said it treats pets free of charge (May 2025): the Unidad de Bienestar Animal (UBA) head office at 7ª avenida 13-21, zona 9, the UBA annex in zona 13 of Guatemala City, and the annex in Zacapa. The UBA reporting line was 1557, extension 7070. These are dated May 2025 details; confirm before you go.
Taking a dog from Guatemala to the United States
APHIS’s page for pet dogs (last modified 1 April 2026) says its Veterinary Services has requirements only for dogs from countries affected by foot-and-mouth disease or screwworm, and its country table lists Guatemala as “not free” of screwworm (and free of FMD). The screwworm rule, as APHIS writes it:
“If your pet dog is coming from a country or region where screwworm is known to exist, it may enter the United States only if it is accompanied by a certificate signed by a full-time salaried veterinary official (official government veterinarian) of the region of origin stating that the dog: Has been inspected for screwworm within 5 days before shipment to the United States, and Is either free from screwworm or Was infested with screwworm, held in quarantine, and treated until free from screwworm before leaving the region.”
What that means in practice, on APHIS’s own text:
| Point | What APHIS says |
|---|---|
| Who signs | A full-time salaried official government veterinarian of the region of origin |
| Timing | Inspection within 5 days before shipment |
| What it states | Free from screwworm, or infested, quarantined and treated until free before leaving |
| Form | No required template; standalone, or incorporated into an export health certificate issued in the exporting country |
| At arrival | Documentation reviewed and the dog inspected at the port of entry |
| Getting the endorsement | Contact the animal-health competent authority of the country the pet travels from |
The Mexico-only exception, a clinical vet authorised to sign on the official vet’s behalf, is stated on the page only for dogs travelling from Mexico.
This is on top of the rabies rules. CDC lists Guatemala as high-risk for dog rabies, which drives the microchip, titre, facility-reservation and six-airport requirements, and MAGA-VISAR’s export certificate is a separate Guatemalan step. All of that is in taking a pet from Guatemala to the USA. Cats are not covered by the APHIS dog rule quoted above.
For people: what CDC publishes
CDC’s outbreak page (dated 11 August 2026) says the current risk to the public in the United States is very low, and that one case was confirmed in August 2025 in a person who returned to the US after traveling to El Salvador. For areas where NWS flies are present, its protection list is:
- Keep open wounds clean and covered, no matter how small or where on the body.
- Wear loose-fitting, long-sleeved shirts and pants, hats, and socks.
- Use an EPA-registered insect repellent.
- Treat clothing and gear with products containing 0.5% permethrin.
- Sleep indoors or in rooms or tents with screens.
On symptoms, CDC lists: unexplained, painful wounds or sores that do not heal; a foul-smelling odour or bleeding from the site; and seeing maggots or feeling movement in open wounds or sores or in areas such as the nose, mouth, eyes, ears or genitals. Its instruction:
“If you see or feel maggots (larvae) in or on a wound or other area of your body, contact your healthcare provider immediately. They will need to remove all of the maggots, sometimes through surgery. Do not try to remove or dispose of the maggots yourself.”
This page does not add treatment information of its own.
How to report a case in Guatemala
| What | Channel MAGA published | Date published |
|---|---|---|
| Livestock or farm animals with wounds containing larvae | WhatsApp 3570-7727 (MAGA-VISAR), with photos, video and exact location | 6 Nov 2024; repeated 28 May 2025 |
| Dogs, cats and other pets | UBA line 1557, extension 7070 | 28 May 2025 |
MAGA’s November 2024 post also asks owners not to move sick animals.
Sources
- MAGA, “Actuar y detectar, acciones clave a un mes del primer caso de Gusano Barrenador del Ganado”, 29 November 2024 —
https://www.maga.gob.gt/actuar-y-detectar-acciones-clave-a-un-mes-del-primer-caso-de-gusano-barrenador-del-ganado/ - MAGA, “Reportar casos sospechosos de gusano barrenador es clave para evitar su propagación”, 6 November 2024 —
https://www.maga.gob.gt/reportar-casos-sospechosos-de-gusano-barrenador-es-clave-para-evitar-su-propagacion/ - MAGA, “Conozca los lugares disponibles para atención de mascotas afectadas por Gusano Barrenador del Ganado”, 28 May 2025 —
https://www.maga.gob.gt/conozca-los-lugares-disponibles-para-atencion-de-mascotas-afectadas-por-gusano-barrenador-del-ganado/ - MAGA, “Más de 661 mil animales inspeccionados para contener el Gusano Barrenador”, 2 September 2026 —
https://www.maga.gob.gt/mas-de-661-mil-animales-inspeccionados-para-contener-el-gusano-barrenador-2/ - MAGA, “Atienden casos de Gusano Barrenador en perros”, 3 September 2026 —
https://www.maga.gob.gt/atienden-casos-de-gusano-barrenador-en-perros/ - MAGA, “Fortalecen vigilancia para detectar el Gusano Barrenador de forma temprana”, 4 September 2026, and “Personal de salud se prepara para detectar el Gusano Barrenador”, 25 September 2026 —
https://www.maga.gob.gt/fortalecen-vigilancia-para-detectar-el-gusano-barrenador-de-forma-temprana/,https://www.maga.gob.gt/personal-de-salud-se-prepara-para-detectar-el-gusano-barrenador/ - USDA APHIS, “Bring a Pet Dog into the United States” (last modified 1 April 2026) and “Dog Imports: Check Country Disease Status” (last modified 21 January 2026) —
https://www.aphis.usda.gov/pet-travel/another-country-to-us-import/dogs,https://www.aphis.usda.gov/pet-travel/another-country-to-us-import/dogs/disease-status - CDC, “New World Screwworm Outbreak” (11 August 2026) —
https://www.cdc.gov/new-world-screwworm/situation-summary/index.html
All retrieved 2026-09-25; the APHIS and CDC pages were read in a browser because both sites refuse automated downloads.
General information from MAGA, USDA APHIS and CDC as published on the dates shown. Not medical or veterinary advice. En español: Gusano barrenador en Guatemala
Frequently Asked Questions
Is there screwworm in Guatemala?
Yes. MAGA (the Ministerio de Agricultura, Ganadería y Alimentación) reported that the first confirmed case was a calf in Izabal on 29 October 2024, the day the country’s animal-health state of emergency was declared. In a post dated 2 September 2026, MAGA reported that between October 2024 and August 2026 it inspected 661,577 animals and identified 5,169 animals positive for gusano barrenador. USDA APHIS’s dog-import table, last modified 21 January 2026, lists Guatemala as ’not free’ of screwworm.
Can dogs get screwworm in Guatemala?
Yes. In a post dated 3 September 2026, MAGA reported attending reports of possible cases in dogs in four departments: a 13-year-old Golden Retriever in zona 11 of Guatemala City with larvae in a knee-joint wound, a dog with myiasis in Samayac, Suchitepéquez, and preventive treatment for a feral dog in Retalhuleu, while a dog checked in Mixco had no larvae and one in San Pedro Carchá had no active larvae. A MAGA post from May 2025 said that of 97 new cases reported up to 23 May 2025, 23 were dogs and two were cats.
What does my dog need to fly from Guatemala to the United States because of screwworm?
APHIS says a pet dog from a country where screwworm is known to exist may enter the United States only if accompanied by a certificate signed by a full-time salaried veterinary official (official government veterinarian) of the region of origin, stating that the dog was inspected for screwworm within 5 days before shipment, and is either free from screwworm or was infested, held in quarantine and treated until free before leaving. APHIS has no required form; the statements can be a standalone document or part of an export health certificate issued in the exporting country, and the dog is inspected at the port of entry. This is in addition to CDC’s rabies rules.
Can people get screwworm, and what does CDC advise travellers?
CDC reports that Central American countries and Mexico have reported more than 209,400 NWS cases in animals and more than 2,600 cases in people, and that one case was confirmed in August 2025 in a person who returned to the United States after traveling to El Salvador. In areas where NWS flies are present, CDC’s list is: keep open wounds clean and covered, wear loose-fitting long-sleeved shirts and pants, hats and socks, use an EPA-registered insect repellent, treat clothing and gear with 0.5% permethrin, and sleep indoors or in screened rooms or tents. If you see or feel maggots in a wound, CDC says to contact a healthcare provider immediately and not to try to remove them yourself.
How do I report a suspected screwworm case in Guatemala?
MAGA’s Viceministerio de Sanidad Agropecuaria y Regulaciones published the WhatsApp number 3570-7727 for reporting animals with wounds containing larvae, with photos, video and location, and repeated it in May 2025 for farm and livestock animals. For dogs, cats and other pets, the same May 2025 post gave MAGA’s Unidad de Bienestar Animal line 1557, extension 7070.
Where can a pet with screwworm be treated in Guatemala?
In May 2025 MAGA said its Unidad de Bienestar Animal attends pets with gusaneras free of charge at its head office at 7ª avenida 13-21, zona 9, its annex in zona 13 of Guatemala City, and its annex in Zacapa. That list is dated May 2025; MAGA’s own advice in the same post was also to take a wounded pet to your trusted veterinarian.
