Trends in SARS-CoV-2 seroprevalence in Albania during the 2021-2022 pandemic year

Background

Monitoring SARS-CoV-2 seroprevalence dynamics during the COVID-19 pandemic is crucial for understanding population immunity and providing insights into public health policies. Limited data exist on this from Albania and other Eastern European countries. This study aimed to investigate SARS-CoV-2 seroprevalence in Albania, comparing August 2021 and August 2022 data from two representative samples of the general population. The objective was to understand the temporal dynamics of SARS-CoV-2 antibodies across age groups and assess the impacts of natural infection and vaccination on population immunity.

Methods

This longitudinal study was conducted in two consecutive cross-sectional assessments 12 months apart in Albania's urban all-ages population. IgG anti-Spike-1 and anti-Nucleoprotein SARS-CoV-2 antibodies were measured using ELISA, focusing on seropositivity rates and antibody levels.

Methods

The study encompassed 2143 and 2183 individuals in August 2021 and 2022, respectively, with the anti-S1-IgG seropositivity rate escalating from 70.9 ​% to 92.1 ​%. In 2021, seroprevalence ranged from 49.6 ​% (0-15 years) to 82 ​% (>60 years). By August 2022, it surpassed 90 ​% in most age groups, except 0-15 years (73.8 ​%). "Hybrid" immunity (COVID-19+ and Vaccine+) reached 56.6 ​% in 2022, or 2.8 times higher than in 2021, exhibiting the highest antibody levels compared to the only vaccinated or previously COVID-19-infected individuals.

Conclusion

This study highlights an overall 94 % seroprevalence in the Albanian population in August 2022 and robust "hybrid" immunity, suggesting substantial protective immunity against SARS-CoV-2. The lower immunity in the 0-15 age group underscores the necessity for youth-targeted vaccine campaigns. These findings provide valuable insights for shaping healthcare measures and vaccination policies.

Comparative analysis of antibody responses to BNT162b2, ChAdOx1, and CoronaVac vaccines in the Albanian population over the pandemic years 2021 to 2022

This repeated cross-sectional study with two independent sample populations compared the antibody response to severe acute respiratory syndrome coronavirus 2 vaccines in Albania in July-August 2021 and 2022. In 2021, it found higher anti-spike-1 seropositivity and antibody levels in fully vaccinated individuals, especially with BNT162b2 and ChAdOx1 and to a lesser degree with CoronaVac. By 2022, all single-dose recipients showed high antibody responses, suggesting natural infection-enhanced immunity. The study indicates a significant evolution in the antibody response to different coronavirus disease 2019 vaccines and suggests that a single vaccine dose, coupled with natural infection, might suffice to maintain adequate immunity levels in an endemic scenario.

Rapid increase of SARS-CoV-2 seroprevalence during the second half of the COVID-19 pandemic year 2020 in the adult urban Albanian population

Background

This study aims to assess the changes in COVID-19 seroprevalence among the adult urban population of Albania between July and December 2020, when the Wuhan strain of SARS-CoV-2 virus was still prevalent in the country.

Methods

Two independent, randomly selected samples of individuals aged 20-70 years residing in Metropolitan Tirana, Albania, were collected in June-July and December 2020. ELISA method was used for serological testing to determine IgG antibodies anti-S1-SARS-CoV-2. Results: The proportion of individuals classified as seropositive in early July was 7.5% (95% CI: 4.3%-10.7%), which increased 6.5 times in late December 2020, reaching 48.2% (95% CI: 44.8%-51.7%). The increasing seroprevalence rates in the study mirrored the trend of detected COVID-19 cases from June to December 2020 in Albania. However, they demonstrate a much higher cumulative incidence of the SARS-COV-2 infection in the community than the reported COVID-19 cases. Conclusion: The rapid increase in SARS-CoV-2 seroprevalence observed in Tirana City by the end of 2020 was likely a result of several factors, including the very low infection exposure between March-May 2020 when the entire city was in a lockdown, followed by the high susceptibility of the population due to naïve immunity. Despite the high observed seroprevalence at the end of December 2020, COVID-19 incidence continued to increase in Albania through 2021 and 2022 following the new virus variant surges.

Parents' and caregivers' role toward childhood vaccination in Albania: assessment of predictors of vaccine hesitancy

Background

Vaccination has saved millions of lives through the protection of individuals and populations from communicable diseases. Vaccine hesitancy, defined as the delay in acceptance or refusal of vaccines despite the availability of vaccination services, has become a growing global concern. The objective of this study was to investigate parents'/caregivers' hesitancy toward childhood vaccination and its predictors in Albania.

Study design

A cross-sectional survey was conducted.

Methods

The data comes from a survey conducted on a sample of parents/caregivers (89.6% mothers) of children aged 6 months to 8 years at health care vaccination centers in seven Albanian cities from December 2020 to February 2021. Parents/caregivers (one per child) were interviewed by trained healthcare staff using a standardized questionnaire on six main content domains, including immunization behavior, beliefs about vaccine safety and efficacy, attitudes about vaccines, vaccination confidence, estimation of vaccine delay, and the intention to immunize children against SARS-CoV-2, and a self-reported hesitancy. The Albanian Ministry of Health approved the questionnaire, after it was translated, validated and adapted to the local setting. Statistical analyses included independent sample t-tests (p<0.05) and a logistic regression (OR; 95% C.I.).

Results

A total of 475 parents/caregivers of children aged from 6 months to 8 years, attending childhood vaccination in public health services, were interviewed. To the question "how hesitant you are about childhood vaccination", a high number of parents/caregivers (46%) responded that they do not feel hesitant at all, and 32% were not hesitant, a small number of parents/caregivers said they are very hesitant (5%) or somewhat hesitant (12%). A binary logistic model was fitted to the data to test the hypothesis regarding the relationship between parental vaccine hesitancy and possible predictors. A lower parental attitude toward childhood vaccines (OR = 3.7; 95% C.I. 1.102-12.421), a health center with a high vaccine delay (OR = 2.878; C.I. 95% 1.735-4.773), and low confidence in health staff information (OR = 2.042; 95% C.I. 1.156-3.605) were all independent predictors of parental vaccine hesitancy. Regarding intention to vaccinate children against COVID-19, when available, nearly 75% of parents/caregivers showed hesitancy.

Conclusions

Our results highlighted the role of positive parents'/caregivers' attitudes toward childhood vaccines followed by high staff confidence and good health center organization in order to deal with vaccine hesitancy, particularly for traditional and well-known childhood vaccines. Nevertheless, the hesitancy can be a critical barrier for childhood vaccination when we have to introduce a new vaccine, as is demonstrated in the recent vaccination campaign against the ongoing pandemic of SARS-CoV2.

Circulation of Enteric Viruses in Tirana, Albania: Situation Ten Years After the First Study

A variety of enteric bacteria, viruses and protozoa are the leading causes of morbidity and mortality worldwide. To understand the evolution of gastroenteritis in Albania, in terms of distribution of aetiological pathogens, a one-year observational study was repeated in 2017, ten years after the first study performed in 2007. The data still show a clear circulation of viruses that cause gastroenteritis. Compared to the previous study in 2007, the data from the 2017 study showed the incidence of Norovirus and Adenovirus were significantly higher (p value <0.05), while Rotavirus was verified at a similar incidence rate.

Transitional challenges of Medicine and Surgery in Albania

Data on the State of Art of Medicine and Surgery in Albania, are given in this short survey. From recent epidemiological data, conditioned by high rate of migration and territory problems, to problems arising from lack of technological supports and important changes in medical education. An analysis that we could do from the observatory of our Medical School, and international one, based on a strict collaboration among an international professor staff, mostly coming from Italian Universities, particularly the University of Rome, "Tor Vergata", co-founder of the "Catholic University Our Lady of Good Counsel" (UCNSBC). The integration between academics in UCNSBC and health personnel in health care offers some interesting opportunities in research. The recognized limited technological supports create the possibilities to adjust and ameliorate health care services, with the aim of a more convenient distribution of the available resources.

KEY WORDS

Academic education, Albania, Epidemiology, Health education.

Molecular characterization of norovirus GII strains identified in Albania

Noroviruses (NoVs) are considered as the leading cause of diarrheal diseases in all groups of age. In the last decade the number of NoV outbreaks worldwide is increasing. Data published by the systems of NoV surveillance show the GII.4 strain as the human predominant genotype circulating worldwide and new genetic variants of GII.4 were associated with epidemic events. In Albania the economy transformation has damaged significantly the environment and a large circulation of enteric viruses was reported in the past with the presence of NoV among the genotyped strains. This study aimed to characterize, by molecular analysis, the NoV GII strains detected in Albania during two time periods: in 2010 from the outbreak occurred in Ballsh and in 2002-2003 from sporadic cases of diarrhoea. A total of 21 Nov GII strains were characterized. The NoV GII.4 was genotyped more frequently and it was related closely to the pandemic variants recorded in GenBank. During 2002-2003, six NoV GII recombinant strains have been characterized.

First outbreak of norovirus in Albania

AIMS

Noroviruses (NoVs) represent the most important enteric viruses responsible for acute gastroenteritis world-wide. This study objective is to characterize the first outbreak of NoV that occurred in Ballsh, a small city in Albania.

METHODS AND RESULTS

Stool specimens were collected from people attending to the hospital. Samples were also collected from the aqueduct for bacteriological and virological tests. Overall 33 stools and five drinking water samples were collected, respectively, from the hospital in Ballsh and from the municipal aqueduct. No water samples were scored positive whereas ten stool samples (30.3%) were scored GGII NoV positive. All the GGII isolates were identified as GGII·4 genotype, and no GGI was identified. The alignment and protein analysis were performed using, respectively, ClustalV and the mega 4 software.

CONCLUSIONS

This is the first report of NoV GGII·4 in Albania causing an outbreak. The genetic analysis showed several point mutations and amino acid substitutions with respect to the international strains.

SIGNIFICANCE AND IMPACT OF STUDY

Over the last decades, Albania has suffered from different outbreaks as cholera, poliomyelitis, hepatitis A and now, for the first time, it has been documented an outbreak of NoV.

[A child health promotion intervention in Albania: results and lessons learned]

Albania is a Balkan country in South-Eastern Europe which, in recent years, has undergone complex demographic, political and economical changes. A notable drop in infant and maternal mortality rates and a significant rise in economic indicators have been observed in recent years. Despite this, over 15% of the population living in the northern and north-eastern areas of the country lives in extreme poverty conditions. In recent years various healthcare system reforms have been introduced, including the introduction of private healthcare and improvement of the main hospital infrastructures but not much has been done to increase the provision of essential healthcare services especially in rural and poor areas. Inequalities in health care are therefore widespread and these particularly affect children living in critical areas. In this paper we describe a paediatric healthcare intervention programme conducted in Albania from 2002 to 2004, aimed at improving the health and nutrition status of children and tackling healthcare system inequalities. The intervention consisted in offering free healthcare services and assistance, delivered through the Albanian healthcare system, to 5280 children. It also involved a health education programme for the mothers. The impact of the programme on the prevalence of infant malnutrition was evaluated by examining the medical records of 1745 infants followed for at least 6 months. Prevalence of malnutrition significantly decreased, from 13.4% to 4.2% during the study period. Mortality in children aged 0-5 years also showed a considerable drop. These results confirm that an efficient and sustainable model of paediatric healthcare assistance in Albania is possible.

Prevalence and genotyping of human isolates of Giardia duodenalis from Albania

Microscopical and PCR-based techniques were performed in order to investigate the prevalence of infection and the genotypes of Giardia duodenalis from 125 stool samples collected from children living in the urban and the rural areas of Tirana (Albania) and hospitalized with acute gastroenteritis. 7 out of 125 samples resulted positive for Giardia at the microscopic examination (5.6%). In 50 selected samples including the 7 samples positive for Giardia by microscopy, 3 and 15 additional positive samples were detected by immunofluorescence and PCR, respectively. Seasonality appeared as an important parameter to be evaluated in order to better understand the prevalence of infection. Sequence analysis revealed both human Assemblage A and B. This result represents the first data on G. duodenalis genotypes in Albania.

Nucleotide correlation between HAV isolates from human patients and environmental samples

Hepatitis A disease is endemic in Albania even though records from the Medical Authority show outbreaks involving only limited numbers of people. In the city of Lac, 200 people became ill following an outbreak of hepatitis A started on November 2002. The age distribution of the cases shows a peak in the age group 5-9 (43.5%) followed by the age group 10-14 (28%) and the age group 1-4 (18%). No cases were recorded in the age group 0-1. Drinking water and sewage samples were collected, using electropositive cartridges, during the outbreak. Rotavirus was identified by RT-PCR in two out of five drinking water samples; however, all the samples tested negative for HAV and astrovirus. Rotavirus was also identified in three out of five sewage samples from which four were HAV positive. HAV-RNA was identified in 28 (62.2%) out of 45 IgM anti-HAV positive sera collected during the outbreak. Genotype IA was expressed from all the amplified samples. Sequence analysis of the overlapping VP1-2A region shows 97-99% homology with three Italian strains IT-SCH-00, IT-ZAM-01, and IT-CAP-00 and one Spanish strain (Sa 30/06/95), whereas the phylogenetic tree built from the 168 bp sequence of the VP1-2A shows four clusters, one including 24 out of 28 RT-PCR positive sera. Considering the deduced amino acid sequence, only one substitution was identified and reported previously for genotype IB.

Iron deficiency anemia and feeding practices in Albanian children

Iron deficiency is the most prevalent nutritional problem of humans. In northern Albania, nutritional deficiencies are widespread among children but there is a lack of biochemical data. The aim of this study was to assess the prevalence rate of the iron deficiency anemia in a sample of northern Albanian children. A group of 112 children aged 6-60 months, recruited during the routine vaccinations, was enrolled in a cross-sectional health examination survey that included venou blood measurements of iron status. The survey was conducted during 2000 in Lezha District. The mean age was 17.1 +/- 10 months, the majority of the children were living in rural areas (61%), 47.8% were female. The mean level of hemoglobin was lower than the reference value (10.3 +/- 1.1). Iron deficiency Anemia occurred in 47 children (47%) and more likely during the first year of the life (51%). Fifty seven children were fed with whole cow's milk, among them 44 were IDA. The risk value to be anemic or iron deficient for infants aged 6 to 12 months that were fed with whole cow's milk before the fourth months of life was high (OR = 6.2 (C.L.1.0-38)). In conclusion, the high prevalence of IDA and the relationship with early feeding of whole cow's milk suggest to consider iron deficiency in infancy and childhood in Albania as an important nutritional public health problem and to implement strategies for his detection, treatment and prevention.

Hepatitis in Albanian children: molecular analysis of hepatitis A virus isolates

Hepatitis A is a common disease in developing countries and Albania has a high prevalence of this disease associated to young age. In spite of the occurrence of a unique serotype there are different genotypes classified from I to VII. Genotype characterisation of HAV isolates circulating in Albania has been undertaken, as well as the study of the occurrence of antigenic variants in the proteins VP3 and VP1. To evaluate the genetic variability of the Albanian hepatitis A virus (HAV) isolates, samples were collected from 12 different cities, and the VP1/2A junction amplified and sequenced. These sequences were aligned and a phylogenetic analysis performed. Additionally, the amino half sequence of the protein VP3 and the complete sequence of the VP1 was determined. Anti-HAV IgM were present in 66.2% of all the sera. Fifty HAV isolates were amplified and the analysis revealed that all the isolates were sub-genotype IA with only limited mutations. When the deduced amino acid sequences were obtained, the alignment showed only two amino acids substitutions at positions 22 and 34 of the 2A protein. A higher genomic stability of the VP1/2A region, in contrast with what occurs in other parts of the world could be observed, indicating high endemicity of HAV in Albania. In addition, two potential antigenic variants were detected. The first at position 46 of VP3 in seven isolates and the second at position 23 of VP1 in six isolates.

A large infantile gastroenteritis outbreak in Albania caused by multiple emerging rotavirus genotypes

By the end of December 2000, the epidemiological system 'Alert' of the Public Health Institute in Tirane reported an outbreak of acute gastroenteritis. The outbreak involved children in Tirane and in the rural area. In total, 2722 children were seen in Tirane Hospital and 982 (56.4%) were treated for acute gastroenteritis. The age group with the highest morbidity was 0-5 years (89.7%), followed by the 6-9 (6.2%) and 10-15 years age groups (4.1%). The distribution of acute gastroenteritis cases, which occurred along the same water distribution system, suggests a waterborne origin. The nucleic acid amplification confirmed the co-circulation of different genotypes of rotavirus, mainly P[8]G9 and P[8]G3, responsible for the outbreak. Other enteric viruses such as astrovirus serotype 1, adenovirus and Norovirus, genogroups I and II were detected. Co-infections with different rotavirus genotypes and even with different enteric viruses were detected in several samples.

Waterborne gastroenteritis outbreak in Albania

Three different studies are reported concerning the environmental pollution caused by viruses in Albania. The first study describes an outbreak of gastroenteritis in the capital city, involving 2,722 children attending the Paediatric Unit of Tirana Hospital. The age group with the highest morbidity was 0-5 years, with 89.5%; no fatalities were recorded during the outbreak. Rotavirus was detected in 26/28 faecal samples by RT-PCR, although astrovirus, adenovirus and calicivirus were also present. The second study describes an outbreak of hepatitis A virus involving the city of Lac. Two hundred cases were recorded, with the highest incidence in the age-group 5-9 years. Phylogenetic analysis of the VP1/2A region showed the presence of a unique sequence: genotype IA. Rotavirus was identified in drinking-water samples collected during the outbreak. The third study describes the prevalence of HAV and HEV in 202 sera randomly collected from 12 different cities in Albania. HAV showed a high incidence (66.2%), whereas none was positive for HEV. The genomic analysis of the VP1/2A junction revealed the presence of only one genotype (IA) with few point mutations and just two amino acid substitutions at codons 22 and 34. Additionally, two potential antigenic variants were detected, the first at position 46 of VP3 and the second at position 23 of VP1.

Tirane, Albania: survey on drinking water quality and facilities

To develop a realistic model of the situation, a study was carried out in four different socioeconomic and hygienic areas of Tirane, namely in the modern and historical centre as well as in the intermediate and peripheral areas. In each area interviewers from the city's Public Health Directorate, contacted randomly, door-to-door, the residents, submitting a questionnaire and collecting water samples at the same time. Our data show relevant differences regarding distribution and quality of drinking water between the centre and peripheral areas. One third of water samples revealed the presence of microorganisms, whereas one fifth had no residual chlorine. Altogether more than 200,000 people in the peripheral areas of Tirane live under low level hygienic conditions. The recent outbreaks of cholera, poliomyelitis and the hyperendemic hepatitis A disease are the dramatic results of the low quality drinking water.