Table 2.
List of surveillance studies of swimming pools (SPs), and respective cases and outbreaks of infections associated with swimming pools and hot springs in tropical and subtropical countries.
| Microsporidia | |||
| Location/Country | Type of Research | Positive Results | Reference |
| Rural areas, Bangladesh | Report of an incident of a traveller from Bangladesh returning to Paris, France | A man suffered from bilateral keratitis after bathing in a rural pond. The patient was found to be infected with a microsporidial parasite belonging to the genus Nosema. | [41] |
| Taipei, Taiwan | Retrospective study of patients diagnosed with microsporidial keratitis | All patients were known to have contracted microsporidial keratitis after bathing in hot springs. | [42] |
| Schistosoma spp. | |||
| Location/Country | Type of Research | Positive Results | Reference |
| Dogon Valley, Mali | Study of an acute schistosomiasis in Belgian travellers returning from Dogon Valley, Mali | 8/13 travellers infected with Schistosoma. 5/8 travellers had experienced swimmer’s itch and developed Katayama syndrome. | [55] |
| Belo Horizonte, State of Minas Gerais, Brazil | Study of an outbreak of acute schistosomiasis in a holiday resort at an endemic area | 17 cases infected with S. mansoni. | [56] |
| São João del Rei, Brazil | Study of an outbreak where an area became infected due to influx of infected workers from endemic areas, who infected water sources, including SPs | 50 workers infected in the pool with S. mansoni. | [57] |
| Upper Benue Valley, North Cameroon | Study of the risk factors for human schistosomiasis in the local population | High prevalence of the disease depending on, among other factors, the intensity of contact with the water. | [58] |
| Dogon Valley, Mali | Study of an outbreak in two groups of 30 Dutch travellers returning from Dogon area of Mali where they swam in fresh water pools | 29 infected with S. intercalatum, S. haematobium. | [59] |
| Cryptosporidium spp. | |||
| Location/Country | Type of Research | Positive Results | Reference |
| Beijing, China | Survey of 35 randomly selected hotel SPs, 60 water samples | 16.7% positive for Cryptosporidium, 15% positive for Giardia. | [66] |
| Various areas, Philippines | Survey of water sources including SPs | 33% positive for Cryptosporidium. | [77] |
| Broome, Kimberley region, Western Australia | Investigation of outbreak of cryptosporidiasis | 11/18 cases swam in the public pool. In faecal and pool water samples Cryptosporidium ominis was identified. | [78] |
| Acanthamoebae & Naegleria Species | |||
| Location/Country | Type of Research | Positive Results | Reference |
| Mexico City, Mexico | Survey of six swimming pools | All SPs were positive for Acanthamoebae. The most commonly found were Amoebae of the species Naegleria gruberi Schardinger. | [84] |
| Taichung, Taiwan | Diagnosis of fatality | One fatal case of meningoencephalitis caused by N. fowleri and transmitted in hot springs was reported. | [85] |
| Alexandria, Egypt | Survey of two SPs | Both SPs were positive for Acanthamoeba spp. and Naegleria spp. | [86] |
| Kuala Lumpur, Malaysia | Survey of 14 pools. Four water samples and six samples using swabs were collected from each | Acanthamoeba species were detected in all sampling sites of all SPs, while Naegleria spp. was detected in 3 sampling sites of 8 SPs. | [87] |
| Mexico City, Mexico | Survey of three physiotherapy tubs and 11 SPs | All therapy tubs were positive for Acanthamoeba spp., while 7/11 SPs were positive for Naegleria spp. | [88] |
| Brazil, Porto Alegre | Survey of 65 water samples from SPs | Amoebae were detected in 20% of the SPs. 4/65 water samples were positive for Acanthamoeba spp. while 9/65 water samples were positive for free-living amoebae. | [89] |
| Egypt, various locations | Survey in various waters including two SPs | 49.2% of pool water samples were positive for heat-tolerant Acanthamoeba spp. | [90] |
| Porto Alegre, Brazil | Survey in pools and spas | 8/72 water samples were positive for Acanthamoeba spp. distributed in group genotypes T3, T5, T4, T15. | [91] |
| Brasilia District, Brazil | Study of the pathogenicity of strains from environmental sources | 4/4 Acanthamoeba spp. isolates from pool waters were pathogenic. | [92] |
| Ahwaz, Iran | Survey of 110 water and soil samples including four SPs | In 71.6% of water samples Acanthamoeba spp. was detected SP isolates belong to T4 genotype. | [93] |
| Various areas, Philippines | Survey of rivers, ponds, dispensers, wells, taps, natural lakes and SPs | 33.3% of SP water samples were positive for Acanthamoeba sp. While 9.1% of SP water samples were positive for Naegleria spp. | [77] |
| Adana, Afyon, Kutahya, Mersin and Nigde provinces, Turkey | Survey of hot springs and SPs | 42% of water samples were positive for Acanthamoeba sp. belonging to T3, T4, T5 genotypes. | [94] |
| Malaysia Peninsular | A survey of recreational lakes, streams, SPs | Naegleria sp was detected in all samples. | [95] |
| Leptospira spp. | |||
| Location/Country | Type of Research | Positive Results | Reference |
| Various places, Dominican Republic | Study of leptospirosis in travellers | A German woman developed leptospirosis after swimming in a chlorinated SP. | [105] |
| Viruses | |||
| Location/Country | Type of Research | Positive Results | Reference |
| Queensland, Australia | Study of a primary school outbreak of pharyngo-conjunctival fever attributed to swimming in the SP of a school camp | 40% of the students infected by Adenovirus type 3. | [114] |
| Pretoria, South Africa | A study of the risk of infection of HAdVs detected in a survey of 3 SPs, 92 water samples | HAdVs were detected in 15 samples. | [115] |
| Porto Alegre, Brazil | Survey of SPs for the detection of adenoviruses in Acanthamoeba strains | 16 Acanthamoeba strains were detected, HAdVs were detected in 62.5% (10/16) of Acanthamoeba isolates. | [116] |
| South Africa | Investigation of an outbreak related to swimming in the school camp pool | 90 children & the SP water were positive for Echovirus 3. | [117] |
| Taiwan, various areas | A study to determine the prevalence of HAdVs in hot springs. 57 hot springs and 14 public SPs were investigated, 57 water samples | HAdVs were detected in 28.1% of the samples from hot springs and 21.4% of SP water samples. | [118] |
| Beijing, China | A study of an outbreak of pharyngoconjunctival fever related to swimming in a University SP | 50 patients used the same SP. HAdV type 4 was identified from the patients and SP water samples. | [119] |
| Vectors | |||
| Location/Country | Type of Research | Positive Results | Reference |
| Malindi, Kenya | A systematic review of the factors contributing to urban transmission of malaria in Sub-Saharan Africa | Anopheles gambiae proliferating in SPs. Artificial rather than natural breeding sites provide most abundant sources for mosquito larvae. | [132] |
| Malindi, Kenya | A study on larvae surveys in urban environments and the productivity of unused SPs in relation to other habitats | Unused SPs accounted for 42.7% of all 110 positive habitats. Anopheles gambiae s.l. and Culex quinquefasciatus were detected. | [133] |
| Malindi, Kenya | A study on the abundance of immature Anopheles and culicines in various water body types in the urban environment | Unused SPs comprised 21.7% of water bodies serving as habitats for immature Anopheles. | [134] |
| Dakar, Senegal | An entomological survey on the determinants of malaria transmission in the city of Dakar | 355 private properties were visited, including SPs. Culicidae larvae were found in 80 (23%) and Anopheles larvae in 11 (3%). | [135] |
| Sao Jose de Rio Preto, Brazil | A study on the evaluation of two sweeping methods for estimating the number of immature Aedes aegypti | Aedes aegypti was harvested in various types of containers including SPs. | [136] |