Antiviral drug valacyclovir treatment combined with a clean feeding system enhances the suppression of salivary gland hypertrophy in laboratory colonies of Glossina pallidipes

Particle and Fibre Toxicology

Marc JB Vreysen¹  Andrew G Parker¹  Carmen Marin¹  Adly MM Abd-Alla¹ 

[1] Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Wagramer Straße 5, A-1400 Vienna, Austria

关键词: Hytrosaviridae;    Salivary gland hypertrophy virus;    Glossinidae;    Diptera;   

Others  :  806861
DOI  :  10.1186/1756-3305-7-214

 received in 2014-02-17, accepted in 2014-04-14,  发布年份 2014

【 摘 要 】

Background

Hytrosaviridae cause salivary gland hypertrophy (SGH) syndrome in some infected tsetse flies (Diptera: Glossinidae). Infected male and female G. pallidipes with SGH have a reduced fecundity and fertility. Due to the deleterious impact of the virus on G. pallidipes colonies, adding the antiviral drug valacyclovir to the blood diet and changing the feeding regime to a clean feeding system (each fly receives for each feeding a fresh clean blood meal) have been investigated to develop virus management strategies. Although both approaches used alone successfully reduced the virus load and the SGH prevalence in small experimental groups, considerable time was needed to obtain the desired SGH reduction and both systems were only demonstrated with colonies that had a low initial virus prevalence (SGH ≤ 10%). As problems with SGH are often only recognized once the incidence is already high, it was necessary to demonstrate that this combination would also work for high prevalence colonies.

Findings

Combining both methods at colony level successfully suppressed the SGH in G. pallidipes colonies that had a high initial virus prevalence (average SGH of 24%). Six months after starting the combined treatment SGH symptoms were eliminated from the treated colony, in contrast to 28 months required to obtain the same results using clean feeding alone and 21 months using antiviral drug alone.

Conclusions

Combining valacyclovir treatment with the clean feeding system provides faster control of SGH in tsetse than either method alone and is effective even when the initial SGH prevalence is high.

【 授权许可】

   
2014 Abd-Alla et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

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