We tested an integrated pest management (IPM) strategy to control European foulbrood (EFB) in honey bees. Colonies affected by EFB were assigned to two homogenous groups: an oxytetracycline-treated group (1.5 g OTC/hive) that underwent partial shook swarm (PSS) in combination with queen caging (QC) and an untreated group where only two beekeeping techniques, PSS and QC, were applied. The consumption of sucrose solution, the strength of the colonies, side effects of the mentioned techniques, clinical as well as subclinical relapses of EFB, and the amount of OTC residues in the honey were assessed over a 7-month-long monitoring period. Regarding the consumption of the sucrose solution, there was no significant difference between the OTC-treated and untreated groups. The strength of the untreated colonies was consistently but not significantly higher than those treated with OTC. PSS combined with QC resulted in various side effects in both groups: queen loss (52%), absconding (8%), and drone-laying queen (4%). Untreated colonies (16.7%) showed clinical EFB relapses 4 months after the application of PSS along with QC, while 15.4% of the OTC-treated colonies were confirmed EFB-positive by PCR. OTC residues were detected in the honey yielded in the cases of both groups. Two months after the PSS, the amount of OTC residues in the untreated group was 0.6 ± 0.2 µg/kg, while that in the OTC-treated group amounted to 5.8 ± 11.6 µg/kg; both results are below the maximum residue limit (MRL) of 100 ppb considered in the EU for cascade use.

Background: The use of antibiotics in beekeeping has potential implications for honeybee health and environmental contamination. Recent research indicates that extensive antibiotic use in beekeeping, especially oxytetracycline, promotes antimicrobial resistance in bee-related bacteria. Honeybees can transport oxytetracycline-resistance genes during foraging, potentially establishing reservoirs of resistance in the colony and facilitating intergeneric gene transfer among various gut bacteria as well as in the microbiome of the flowers and the wider environment, where honeybees can spread antibiotic-resistance genes over a large distance. This study investigates the effects of oxytetracycline hydrochloride (OTC) treatment on honeybees from a One Health perspective, examining antibiotic residues in honey, environmental spread, and the presence of tetracycline-resistance genes (TET-RGs). Methods: In the spring of 2022, two groups of four honeybee hives were placed near an almond grove in Central Italy. One group was treated with 1.68 g of OTC, while the other remained untreated. Samples were collected from bees, honey, hive entrances, and flowers before treatment and at 3 as well as 9 days post-treatment. OTC residues and TET-RGs were analyzed to assess contamination and resistance gene dissemination. Results: OTC residues were detected in honey from both treated (day 3: 263,250.0 ± 100,854.3 µg/kg; day 9: 132,600 ± 146,753.9 µg/kg) and untreated hives (day 3: 20.5 ± 8.2 µg/kg; day 9: 135.8 ± 198.6 µg/kg), suggesting cross-contamination. Residues were also found in almond tree flowers (0.7 ± 0.1 µg/kg), with TET-RGs (tet(K), tet(L), tet(M), tet(B), tet(O), tet(D)) detected pre- and post-treatment. In honeybee gut bacteria, resistance genes (tet(M), tet(A), tet(D), tet(B)) appeared post-treatment in both groups. No significant correlation was observed between hive distance and resistance gene presence in flowers, although the presence of other farms located within the bees’ flight range, in which OTC might have been used in the past, could have influenced the results. Conclusions: These findings highlight the risk of OTC-induced antibiotic cross-contamination and the spread of TET-RG, raising concerns for bee health and environmental safety. Given honeybees’ social nature and the negative effects of antibiotics on their health, an antibiotic-free management approach is recommended for sustainable apiculture.

Background/Objectives: In a collaborative effort, FAO, the International Federation of Beekeepers’ Association “Apimondia”, the Appalachian State University, and the Istituto Zooprofilattico Sperimentale del Lazio e Toscana (IZSLT), the FAO Reference Centre for Animal Health and Food Security Discipline Apiculture, health, and biosecurity, designed an online international survey (“Knowledge, Awareness and Practice”-KAP) as a risk assessment tool to validate biosecurity measures able to prevent and control the main honeybee (Apis mellifera subsp.) infectious diseases. Methods: The KAP survey was disseminated through various channels for 14 months (January 2019–March 2020). Beekeepers’ knowledge on nosemosis, American foulbrood (AFB), and European foulbrood (EFB) management was assessed. Beekeepers’ attitudes were investigated by asking them to provide a score called “Acceptance by beekeepers”. Results: Of the 410 respondents, the majority of them (68.3%, n = 252) were from Europe. European beekeepers (n = 252) considered “Highly acceptable” the following practices: removing combs that show signs of dysentery and feeding colonies for nosemosis; the quick identification and management of affected hives for American foulbrood and European foulbrood. Instead, the following practices were considered as not acceptable by beekeepers: for nosemosis, the use of antibiotics and sampling of hive debris for early detection; for American foulbrood and European foulbrood, the shook swarm, the destruction of the whole apiary, as well as their treatment with antibiotics. Conclusion: This study demonstrated the validity of the present “Knowledge, Awareness and Practice” (KAP) survey to validate the best practices for the main infectious honeybee diseases, considering the pragmatic point of view of beekeepers. Sustainable practices for disease control are preferred by the European beekeepers. While having an adequate knowledge base for the early detection of the investigated honeybee diseases, European beekeepers tend to be aware of the health status of their hives, embracing advanced, practice-oriented training. Authors highlight that the selection of practices and their validation should be revised on a regular basis, to be adapted in a timely manner to the current infectious honeybee disease situation, in order to build up a resilient and effective stock of practices.

The small hive beetle (SHB) was first detected in Italy in 2014 and remains confined to the regions of Calabria and Sicily (Italy). The environmental and colony-related factors favorable to the development of SHBs are widely studied, but mainly at the laboratory level; it is not yet clear whether these factors also apply in the field within apiaries in regions affected by SHBs. In 2022, we conducted a study in the province of Reggio Calabria, Italy, to investigate if these factors influence SHB infestation levels in honey bee colonies. Data were collected from 67 hives in late winter and 81 hives in autumn, inspecting each hive three times per season. Overall, SHB infestation levels were low (an average 0.83 SHB/hive). Our analysis revealed a significant relationship between the SHB infestation level and the following six factors: the number of combs covered by adult bees, the total number of combs, combs surveillance, the previous month’s infestation, sun exposure, and season. GLM analysis predicted a higher number of SHBs in colonies with fewer combs covered by adult bees (2.543), with a greater number of combs (1.877), with lower comb surveillance (0.935), with a higher SHB infestation level in the previous month (1.192), in shaded locations compared to sunny ones (0.207), and in autumn compared to late winter (0.258), with peak infestations in September. These findings provide insights to inform surveillance plans, optimise sentinel apiaries setup in SHB-free regions, and offer practical guidance for beekeepers on implementing biosecurity measures to minimise infestation levels and enhance early detection. Future research should examine whether these factors have similar effects in regions with higher SHB infestation rates.

Aethinosis, the honey bee disease caused by small hive beetle, is listed in the Animal Health Law and requires mandatory surveillance and control measures. The Mobile Divider (MD) method has been proposed as a time-saving alternative to the official surveillance method outlined by the Ministry of Health (MoH). The current study aimed to evaluate the efficacy of the MD method in concentrating SHBs behind the MD and optimizing the number of SHBs detected during hive inspections, thereby improving the surveillance strategies required by European regulations and the WOAH. In late winter and autumn 2022, we conducted 431 hive inspections across six apiaries in the province of Reggio Calabria, Italy. A total of 379 adult SHBs were collected and killed; no larvae were detected. Using the MD method, 238 SHBs were found behind the MD, while 141 SHBs were found in the remaining volume of the hive. Chi-square analysis confirmed the effectiveness of the MD method, showing that the SHB distribution behind the MD and in the remaining volume of the hive was not random (p < 0.0005). Further studies are needed to assess the effectiveness and potential benefits of the MD method in regions with higher SHB infestation levels.