Egg data validation in quantitative monitoring of Aedes albopictus in Emilia-Romagna region, Italy

ABSTRACT

The monitoring of Aedes urban species is usually conducted by ovitraps, which can provide a good estimate of population density at low cost and relatively easy management. When the monitoring network is managed by many operators, as in the case of the Emilia-Romagna regional plan, it becomes necessary to develop a quality control methodology capable of highlighting the possible data incoherency and ensuring that the monitoring system provides reliable data.

This paper presents the procedure applied in the egg counting phase as developed in Emilia-Romagna in order to check the data quality and validate the data before being included in the database.

Several steps have been identified and protocols developed to serve quality control such as training of technicians and intralaboratory quality check, daily random double counting of Masonite paddles and interlaboratory periodic comparison.

The qualitative test showed that all operators were able to distinguish Aedes albopictus eggs from other mosquito species eggs. The quantitative test showed significant differences between the 11 operators, with a relative error resulting in the range of 0.1–25.8%.

The daily internal double counting of randomly extracted Masonite slides was performed by the coordinator showing a relative error in the range 2.47–2.63% without statistical differences, confirming a good alignment of the operators with the coordinator throughout the monitoring period.

The interlaboratory comparison trial produced an average relative error of 7.20% showing a sufficient alignment between the three laboratories.

Moreover a new time-saving methods in egg counting was developed and tested in real condition.

KEYWORDS:

• Chikungunya
• dengue
• zika
• quality assessment
• quality control

Acknowledgments

We thank all the technicians that contributed to the field management of the ovitraps as well as those that have participated in the laboratory counting of eggs.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study has been conducted in the frame of the LIFE CONOPS project ‘Development & demonstration of management plans against – the climate change enhanced – invasive mosquitoes in S. Europe’ [LIFE12 ENV/GR/000466] co-funded by the EU Environmental Funding Program LIFE+ Environment Policy and Governance with the support of the Regional Health Authority of Emilia-Romagna.