The slowdown of new infections by human retroviruses has reached a plateau in Spain.

The 2022 annual meeting of the HTLV & HIV-2 Spanish Network was held in Madrid on December 14. We summarize here the main information presented and discussed at the workshop and review time trends for human retroviral infections in Spain. As transmissible agents, infections by human retroviruses are of obligatory declaration. Until the end of 2022, the Spanish national registry had recorded 451 cases of HTLV-1, 821 of HTLV-2, and 416 of HIV-2. For HIV-1, estimates are of 150 000 people currently living with HIV-1 and 60 000 cumulative deaths due to AIDS. During year 2022, new diagnoses in Spain were of 22 for HTLV-1, 6 for HTLV-2, and 7 for HIV-2. The last updated figures for HIV-1 are from 2021 and counted 2786 new diagnoses. The slowdown in yearly infections for HIV-1 in Spain points out that new strategies are needed to achieve the United Nations 95-95-95 targets by 2025. For the remaining neglected human retroviral infections, their control might be pushed throughout four interventions: (1) expanding testing; (2) improving education and interventions aimed to reduce risk behaviors; (3) facilitating access to antiretrovirals as treatment and prevention, including further development of long-acting formulations; and (4) increasing vaccine research efforts. Spain is a 47 million population country in South Europe with strong migration flows from HTLV-1 endemic regions in Latin America and Sub-Saharan Africa. At this time universal HTLV screening has been implemented only in the transplantation setting, following the report of 5 cases of HTLV-associated myelopathy shortly after transplantation of organs from HTLV-1 positive donors. There are four target populations for expanding testing and unveiling asymptomatic carriers responsible for silent HTLV-1 transmissions: (1) migrants; (2) individuals with sexually transmitted infections; (3) pregnant women; and (4) blood donors.

Susceptibility to hepatitis B virus infection in adults living in Spain.

BACKGROUND: A protective hepatitis B virus (HBV) vaccine has been available for four decades. Universal HBV vaccination of infants is recommended by the WHO since the 1990s. Furthermore, HBV immunization is advised for all adults with high-risk behaviours and no seroprotection. However, HBV vaccine coverage remains globally suboptimal. The advent of new more efficacious trivalent HBV vaccines has renewed the interest in HBV vaccination. At present, the extent of current HBV susceptibility in adults remains unknown in Spain. METHODS: HBV serological markers were assessed on a large and representative sample of adults in Spain, including blood donors and individuals belonging to high-risk groups. Serum HBsAg, anti-HBc and anti-HBs were tested in specimens collected during the last couple of years. RESULTS: From 13 859 consecutive adults tested at seven cities across the Spanish geography, overall 166 (1.2%) had positive HBsAg. Past HBV infection was recognized in 14% and prior vaccine immunization in 24%. Unexpectedly, 37% of blood donors and 63% of persons belonging to high-risk groups had no serum HBV markers and therefore were potentially HBV susceptible. CONCLUSION: Roughly 60% of adults living in Spain seem to be HBV susceptible. Waning immunity might be more common than expected. Hence, HBV serological testing should be performed at least once in all adults regardless of risk exposures. HBV vaccine full courses or boosters should be administered to all adults lacking serological evidence of HBV protection.

A Q Fever Outbreak with a High Rate of Abortions at a Dairy Goat Farm: Coxiella burnetii Shedding, Environmental Contamination, and Viability.

This study describes a Q fever outbreak in a herd of 77 Alpine goats which suffered a high rate of abortions (81% [58/72]) in January 2017 and presents the results of monitoring the contamination and viability of Coxiella burnetii in the farm environment several months after the outbreak. Over the course of 7 months, we studied bacterial shedding by 35 dams with abortions to monitor C. burnetii infection dynamics and the duration of excretion. The highest bacterial shedding load was observed in vaginal mucus, followed by in feces and in milk. Conversely, the duration of C. burnetii shedding was longer through feces (5 months after abortion) than milk (3 months). C. burnetii DNA was detected throughout the study in aerosol samples periodically collected indoors and outdoors from the animal premises. Mouse inoculation and culture in Vero cells demonstrated the presence of viable isolates in dust collected from different surfaces inside the animal facilities during the period of time with the highest number of abortions but not in dust collected 2, 3, and 4 months after the last parturition. Some workers and visitors were affected by Q fever, with attack rates of 78% (7/9) and 31% (4/13), respectively. Affected people mostly showed fever and seroconversion, along with myalgia and arthralgia in two patients and pneumonia in the index case. The genotype identified in animal and environmental samples (SNP1/MST13) turned out to be very aggressive in goats but caused only moderate symptoms in people. After the diagnosis of abortion by Q fever in goats, several control measures were implemented at the farm to prevent contamination inside and outside the animal facilities.IMPORTANCE This work describes a 7-month follow-up of the excretion by different routes of Coxiella burnetii genotype SNP1/MST13 in a herd of goats that suffered high rate of abortions (81%), generating high environmental contamination. Some of the workers and visitors who accessed the farm were infected, with fever as the main symptom but a low incidence of pneumonia. The detected strain (SNP1/MST13 genotype) turned out to be very aggressive in goats. The viability of C. burnetii was demonstrated in the environment of the farm at the time of abortions, but 2 months after the last parturition, no viable bacteria were detected. These results highlighted the importance of implementing good biosafety measures at farms and avoiding the entrance of visitors to farms several months after the end of the kidding period.

Q Fever Outbreak among Workers at a Waste-Sorting Plant.

An outbreak of Q fever occurred in February-April 2014 among workers at a waste-sorting plant in Bilbao (Spain). The outbreak affected 58.5% of investigated employees, 47.2% as confirmed cases (PCR and/or serology) and 11.3% as probable cases (symptoms without laboratory confirmation). Only employees who had no-access to the waste processing areas of the plant were not affected and incidence of infection was significantly higher among workers not using respiratory protection masks. Detection by qPCR of Coxiella burnetii in dust collected from surfaces of the plant facilities confirmed exposure of workers inside the plant. Animal remains sporadically detected among the residues received for waste-sorting were the most probable source of infection. After cleaning and disinfection, all environmental samples tested negative. Personal protection measures were reinforced and made compulsory for the staff and actions were taken to raise farmers' awareness of the biological risk of discharging animal carcasses as urban waste.