Paraguay's summer is dengue season. Beyond Asunción, yellow fever is a clinic question.
Paraguay came through a large chikungunya epidemic in 2023 and a dengue epidemic in 2023–24, and the seasons since have been far quieter. A December–April trip lands in the hot, rainy months when dengue spreads. The CDC recommends yellow fever vaccine for any trip beyond the capital, and the country has been certified malaria-free since 2018.
Are there mosquitoes in Paraguay? Yes, and a December–April trip lands in the hot, rainy season when dengue spreads. 2025 and 2026 so far have been far quieter than the large epidemics of 2023 and 2024. The planning item is yellow fever. The CDC recommends the vaccine for every trip that goes beyond Asunción, and the World Health Organization certified Paraguay malaria-free in 2018.
Dengue season, after two big epidemics
A peer-reviewed study published in November 2025 counted 307,058 suspected and 77,675 laboratory-confirmed dengue cases in Paraguay between mid-September 2023 and early May 2024, with 95 deaths. That followed a 2023 chikungunya epidemic in which the Pan American Health Organization counted 83,522 confirmed cases and 297 deaths.
Both have dropped since. PAHO called 2025 a usual, non-epidemic dengue year, with 1,374 confirmed cases, and counted 51 confirmed chikungunya cases. In mid-October 2026, Paraguayan press reports citing the health ministry said suspected dengue notifications were rising in 11 regions, though only two cases had been diagnosed in the previous three weeks. PAHO's October 20 update warned that a strengthening El Niño could favor transmission this season, so check the ministry's dengue updates the week before you fly.
Both viruses spread through Aedes aegypti, which bites in daylight, with peaks after sunrise and in the late afternoon. Put repellent on over sunscreen in the morning, again before sunset and after rain on a warm day. Our dengue & Zika routine has the full schedule. The CDC says chikungunya vaccination is generally not recommended for Paraguay. Its Paraguay page also lists Zika, so if you're pregnant, talk with a healthcare provider before the trip.
Yellow fever: Asunción and everywhere else
PAHO's March 2026 alert lists no yellow fever cases in Paraguay in 2025 or early 2026, and the vaccine isn't required on a direct trip from the US. The CDC still recommends it for every route beyond the capital.
What we suggest you do with this: if your route goes beyond Asunción, to Encarnación, the Jesuit missions, Ciudad del Este or the Chaco, book a travel-medicine appointment 4–6 weeks before departure. The CDC recommends yellow fever vaccine for all travelers 9 months and older going to Paraguay, except that it is "generally not recommended for travel limited to the city of Asunción (the capital)." Tell the clinic if you'll arrive from Bolivia, Brazil, Peru or Venezuela, since Paraguay requires proof of vaccination from travelers 1 year and older coming from those countries.
Many visitors cross from Foz do Iguaçu, in Brazil, to Ciudad del Este on an Iguazú Falls trip. As the CDC words Paraguay's rule, that counts as arriving from Brazil, so ask the clinic how it applies and carry the certificate if you're vaccinated.
The Chaco and the wetlands
Bites get heavier away from the towns. Wildlife tours in the Chaco and the Paraguayan Pantanal, and trips to the Ñeembucú wetlands around Pilar and the Humaitá war sites, draw the most mosquito complaints. The Chaco also has a reputation for extreme summer heat.
The CDC's Paraguay page lists three more risks for rural and ranch stays: leishmaniasis, spread by sand flies that bite from dusk to dawn; Chagas disease, spread by triatomine bugs and tied mostly to rural housing; and New World screwworm, a fly infestation of wounds. For screwworm the CDC advises cleaning and covering all wounds, sleeping in a screened room or under a bed net, and avoiding time around livestock.
Where you're going
Asunción
The CDC generally doesn't recommend yellow fever vaccine for a trip limited to the city, Paraguay's only exception. Dengue returns every summer, and PAHO documented the 2022 chikungunya outbreak here and in Central department. Mosquitoes tend to be worst at dusk and after rain.
Encarnación & the Jesuit missions
Encarnación was the hardest-hit city in Itapúa department in the 2023–24 dengue epidemic, with 1,262 reported cases. The CDC's yellow fever recommendation covers it and the missions at Trinidad and Jesús.
Ciudad del Este, Itaipú & the Iguazú crossing
Inside the CDC's yellow fever recommendation, and arriving from Foz do Iguaçu brings in Paraguay's entry rule for travelers from Brazil. Like other towns in the humid southeast, it tends to have day-biting mosquitoes.
The Chaco: Filadelfia, the Mennonite colonies & Defensores del Chaco
Remote, hot and sparsely populated, and wildlife tour reviewers count mosquitoes among its realities. Pack permethrin-treated long clothes, and on a ranch stay keep any wound clean and covered.
Heading on to Bolivia? Our Bolivia briefing covers its lowlands and its own yellow fever entry rule.
The Paraguay kit
- Picaridin 20% travel sprays: odorless in the heat and layers over sunscreen. One 3.4 oz bottle covers about a week of daily use for one person.
- Permethrin 0.5% for tour clothes: treat a long-sleeved shirt, trousers and socks at home 48 hours before you fly. It goes on clothing, never on skin.
What travelers report
Paraphrased from TripAdvisor threads and reviews and linked so you can read them in full. The tour reviews date from 2021 and 2022, the Asunción thread is undated, and conditions change from one season to the next.
- Ñeembucú (Humaitá war sites) · late April to early May · 2022
A reviewer of a two-week tour around Paraguay (19 April to 3 May 2022) said the mosquitoes in Ñeembucú seemed intent on feasting on their guide at the war sites. TripAdvisor ↗
- Chaco and Paraguayan Pantanal · 2021
A reviewer of a Chaco and Pantanal wildlife tour described the region as rich in wildlife but also full of heat, mosquitoes, dust and potholes. TripAdvisor ↗
- Asunción · August
A traveler asked about mosquitoes in August. A past visitor replied that Paraguay's winter weather varies, that mosquitoes tend to come out just before and just after rain storms on warm days and always at dusk, and that August should be lighter than the warmer months. The reply advised DEET on skin or clothing. TripAdvisor ↗
One rule outlasts the trip. Any fever during or after your trip means a doctor visit, and you tell them you were in Paraguay and which regions you visited.
Traveler questions
Do I need a yellow fever vaccine for Paraguay?
The CDC's recommendation is "Vaccine is recommended for all travelers ≥9 months old except as follows," and the exception is "Vaccine is generally not recommended for travel limited to the city of Asunción (the capital)." So Encarnación, the Jesuit missions, Ciudad del Este and the Chaco are all inside it. Paraguay doesn't require the vaccine on a direct trip from the US. It does require proof from travelers 1 year and older arriving from Bolivia, Brazil, Peru or Venezuela. Book a travel clinic 4–6 weeks before departure to settle it.
I'm crossing from Iguazú Falls in Brazil. Do I need a yellow fever certificate?
The CDC words Paraguay's rule as "Vaccine is required for travelers ≥1 year old arriving from Bolivia, Brazil, Peru, or Venezuela; this includes >24-hour airport transits or layovers in those countries." As written, crossing from Foz do Iguaçu to Ciudad del Este is an arrival from Brazil. Ask a travel clinic how the rule applies to your exact route, and carry the yellow certificate if you have one. The CDC also recommends the vaccine for both sides of the falls; see our Brazil and Argentina briefings.
Is there malaria in Paraguay?
No. The World Health Organization certified Paraguay malaria-free on June 11, 2018. The last P. falciparum case was in 1995 and the last P. vivax case in 2011. The CDC's Paraguay page lists no malaria areas and recommends no malaria medicine.
How bad is dengue in Paraguay right now?
Quiet so far, after a severe 2023–24. A peer-reviewed study counted 307,058 suspected and 77,675 laboratory-confirmed cases and 95 deaths between mid-September 2023 and early May 2024. PAHO called 2025 a usual, non-epidemic year, with 1,374 confirmed cases. In mid-October 2026, Paraguayan press reports citing the health ministry said suspected notifications were rising in 11 regions, though only two cases had been diagnosed in the previous three weeks and there were no active outbreaks. PAHO warns that El Niño could favor transmission this season, so check the ministry's updates before you fly. Our dengue bite guide covers what to watch for afterward.
Sources
Health authorities, surveillance reports and news coverage of official bulletins used for this briefing, last checked October 2026. Traveler reports are linked where they appear. This page summarizes public-health guidance and is not medical advice.
- Peer-reviewed study (PubMed Central)
- Pan American Health Organization (PAHO)
- Pan American Health Organization (PAHO)
- ultimahora.com
- abc.com.py
- hoy.com.py
- ultimahora.com
- CDC destination page for travelers
- CDC Travel Health Notice
- Pan American Health Organization (PAHO)
- Pan American Health Organization (PAHO)
- ultimahora.com
- Pan American Health Organization (PAHO)
- World Health Organization
- Pan American Health Organization (PAHO)
- abc.com.py