Molecular analysis of dolphin morbillivirus: A new sensitive detection method based on nested RT-PCR

Area of Science:

• Marine Mammal Health
• Virology
• Molecular Diagnostics

Background:

• Cetacean Morbillivirus (CeMV) is a highly pathogenic RNA virus causing lethal outbreaks in whales.
• Detecting CeMV RNA in stranded cetaceans is difficult due to poor tissue preservation.
• Nested RT-PCR enhances sensitivity and specificity for viral RNA detection.

Purpose of the Study:

• To develop a novel nested RT-PCR technique for amplifying low-quantity CeMV RNA in whale tissues.
• To assess the applicability of this technique on various tissues from stranded marine mammals.

Main Methods:

• A new nested RT-PCR protocol was designed to amplify cDNA of CeMV.
• The method was applied to lung, brain, spleen, and lymphoid tissues from eight marine mammals.
• Sequencing of a 200 bp fragment of the dolphin Morbillivirus (DMV) haemagglutinin (H) gene confirmed CeMV presence.

Main Results:

• The new nested RT-PCR successfully amplified CeMV RNA from all eight marine mammal samples.
• The technique proved effective even with scant viral RNA in poorly preserved tissues.
• Sequencing confirmed CeMV (DMV) presence in all analyzed specimens.

Conclusions:

• The developed nested RT-PCR protocol is a sensitive and cost-effective method for CeMV detection.
• This technique is valuable for diagnosing CeMV in compromised marine mammal tissue samples.
• The protocol is relatively inexpensive and easy to implement for diagnostic laboratories.