Remarkable richness of trypanosomes in tsetse flies (Glossina morsitans morsitans and Glossina pallidipes) from the Gorongosa National Park and Niassa National Reserve of Mozambique revealed by fluorescent fragment length barcoding (FFLB)

Infect Genet Evol. 2018 Sep;63:370-379. doi: 10.1016/j.meegid.2017.07.005. Epub 2017 Jul 5.

Abstract

Trypanosomes of African wild ungulates transmitted by tsetse flies can cause human and livestock diseases. However, trypanosome diversity in wild tsetse flies remains greatly underestimated. We employed FFLB (fluorescent fragment length barcoding) for surveys of trypanosomes in tsetse flies (3086) from the Gorongosa National Park (GNP) and Niassa National Reserve (NNR) in Mozambique (MZ), identified as Glossina morsitans morsitans (GNP/NNR=77.6%/90.5%) and Glossina pallidipes (22.4%/9.5%). Trypanosomes were microscopically detected in 8.3% of tsetse guts. FFLB of gut samples revealed (GNP/NNR): Trypanosoma congolense of Savannah (27%/63%), Kilifi (16.7%/29.7%) and Forest (1.0%/0.3%) genetic groups; T. simiae Tsavo (36.5%/6.1%); T. simiae (22.2%/17.7%); T. godfreyi (18.2%/7.0%); subgenus Trypanozoon (20.2%/25.7%); T. vivax/T. vivax-like (1.5%/5.2%); T. suis/T. suis-like (9.4%/11.9%). Tsetse proboscises exhibited similar species composition, but most prevalent species were (GNP/NNR): T. simiae (21.9%/28%), T. b. brucei (19.2%/31.7%), and T. vivax/T. vivax-like (19.2%/28.6%). Flies harboring mixtures of trypanosomes were common (~ 64%), and combinations of more than four trypanosomes were especially abundant in the pristine NNR. The non-pathogenic T. theileri was found in 2.5% while FFLB profiles of unknown species were detected in 19% of flies examined. This is the first report on molecular diversity of tsetse flies and their trypanosomes in MZ; all trypanosomes pathogenic for ungulates were detected, but no human pathogens were detected. Overall, two species of tsetse flies harbor 12 species/genotypes of trypanosomes. This notable species richness was likely uncovered because flies were captured in wildlife reserves and surveyed using the method of FFLB able to identify, with high sensitivity and accuracy, known and novel trypanosomes. Our findings importantly improve the knowledge on trypanosome diversity in tsetse flies, revealed the greatest species richness so far reported in tsetse fly of any African country, and indicate the existence of a hidden trypanosome diversity to be discovered in African wildlife protected areas.

Keywords: African trypanosomes; DNA barcoding; T. brucei; T. congolense; T. godfreyi; T. simiae; T. suis; T. vivax; Tsetse flies; Wildlife.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Wild / parasitology
  • Artiodactyla / parasitology
  • DNA Barcoding, Taxonomic / methods*
  • Genetic Variation*
  • Genotype
  • Humans
  • Intestines / parasitology
  • Livestock / parasitology
  • Mozambique
  • Parks, Recreational
  • Perissodactyla / parasitology
  • Trypanosoma / classification
  • Trypanosoma / genetics*
  • Trypanosoma / isolation & purification
  • Trypanosoma / pathogenicity
  • Trypanosoma brucei brucei / classification
  • Trypanosoma brucei brucei / genetics*
  • Trypanosoma brucei brucei / isolation & purification
  • Trypanosoma brucei brucei / pathogenicity
  • Trypanosoma congolense / classification
  • Trypanosoma congolense / genetics*
  • Trypanosoma congolense / isolation & purification
  • Trypanosoma congolense / pathogenicity
  • Trypanosoma vivax / classification
  • Trypanosoma vivax / genetics*
  • Trypanosoma vivax / isolation & purification
  • Trypanosoma vivax / pathogenicity
  • Tsetse Flies / classification
  • Tsetse Flies / parasitology*