The Serengeti's biters work in shifts: tsetse by day, mosquitoes after dark.

Yes, though the biter you'll notice first is the tsetse fly, which works the Serengeti's woodlands by day. Mosquitoes take over after dusk and bring the malaria question. The CDC recommends prevention medicine for all of Tanzania below 5,900 feet, and every Serengeti itinerary spends time below that line.

The malaria line on a Northern Circuit safari

The CDC gives Tanzania's malaria areas as "All areas below 1,800 m (5,900 ft) elevation." Most of the Serengeti lies below that line. A night on the Ngorongoro Crater rim doesn't change the picture, because Arusha, Karatu, Tarangire and the Serengeti plains are all lower.

Yellow fever vaccine is generally not recommended, but Tanzania requires proof from travelers arriving from a risk country, which matters if you cross from Kenya's Maasai Mara. CDC's Level 2 Global Polio notice lists Tanzania, so be up to date on polio vaccine.

Tsetse flies and sleeping sickness

The Serengeti has two tsetse species, Glossina swynnertoni and G. pallidipes, and they live in large numbers in its savannah and woodland. Forum posters describe the park as patchy, with few tsetse at central Seronera and more around Lobo and Kusini. Tsetse bite by day and home in on moving vehicles and on dark blue and black, so game drives through wooded country are the main exposure.

The CDC lists African sleeping sickness, which tsetse spread, for Tanzania. The Serengeti is a long-standing focus of the disease, with cases in local people and tourists. In early 2001, nine European and South African travelers got sleeping sickness after visiting Tarangire and the Serengeti, and Tanzania responded with insecticide-treated targets at roads, lodges and campsites, after which tsetse numbers fell sharply. A 2012 study found very few infected tsetse around Seronera and judged the risk to tourists low, in line with fewer than 5 cases a year reported in the Serengeti against almost 100,000 visitors.

Wear long sleeves and trousers in khaki, olive or tan, and ask your guide to steer around known tsetse pockets.

Camp evenings

Malaria mosquitoes bite in camp from dusk to dawn. Tented camps vary in how well they seal, so check the zips and the net on arrival and sleep under it. Put on picaridin 20% or DEET 20–30% before sundowners and wear long sleeves for dinner. On walking safaris, tuck trousers into socks and check for ticks afterward; the CDC lists African tick-bite fever for Tanzania.

When to go

The herds usually calve on the southern plains around Ndutu from about January to March, move west into the Grumeti and western corridor around May to July, reach the northern Serengeti and the Mara River around July to October, and drift south with the short rains in November and December. Mosquitoes tend to increase with the long rains, roughly March to May, and the short rains, which overlap the wet end of calving season. The CDC's malaria advice applies all year.

Where you're going

Our Tanzania briefing covers Tarangire, the circuit's strongest tsetse park, and Kilimanjaro, and the Zanzibar briefing covers a beach finish.

What travelers report

Paraphrased from a TripAdvisor forum thread and a lodge review and linked so you can read them in full. Neither is dated, and the season, the sector and how well your room seals change the picture.

• Northern Circuit parks (Tarangire, Serengeti, Ngorongoro, Arusha NP)

  Posters ranked parks by tsetse: Tarangire was the most consistent hotspot with many pockets in bushy areas, the Serengeti was patchy (few at Seronera, more around Lobo and Kusini), and Ngorongoro Crater and Arusha National Park had few or none. They disagreed on which season is worst and advised avoiding dark blue and black clothing. TripAdvisor ↗

• Singita Sasakwa, western Serengeti

  A two-night guest said they were bitten more than at any other lodge they had visited, by tsetse flies during the day and mosquitoes at night, and faulted the lodge's insect-proofing of rooms rather than the area's tsetse. Management replied that it is aware of the challenges insects, particularly tsetse flies and mosquitoes, pose in the region. TripAdvisor ↗

One rule outlasts the trip. Any fever during or after your trip means a doctor visit and a malaria test, and you tell the doctor which parks you visited and whether tsetse bit you. With malaria in the picture, the rule holds for a full year.

Traveler questions