Figure 1:
Subgroup meta-analysis of experimental studies reporting Dirofilaria immitis infected and infective rates in vectors grouped by mosquito genus and species_
| Minimum infected ratea | Minimum infective rateb | ||||||
|---|---|---|---|---|---|---|---|
| Variable | Pool size | Positive pool | Overall prevalence (95% CI) | I 2 | Positive pool | Overall prevalence (95% CI) | I 2 |
| Overall | 4,512 | 1,524 | 379.9 (154.5-636.5) | 89.2 | 251 | 84.7 (20.5-183.8) | 98.8 |
| Method PCR | 271 | 161 | 649.2 (459.5-817.8) | 99.7 | 44 | 194.6 (55-388.8) | 99.4 |
| Method Dissection | 4,241 | 1,363 | 253.7 (40.4-565.7) | 99.6 | 207 | 46.9 (0.9-147) | 99.1 |
| Ae. spp. | 1,506 | 905 | 482.2 (105.2-871.6) | 99.6 | 168 | 132.4 (17.3-324.2) | 98.5 |
| Cx. spp. | 2,893 | 561 | 61.2 (0.5-197) | 98.8 | 65 | 55.9 (2.7-163.1) | 98.2 |
| An. spp. | 90 | 58 | 644.4 (536.5-742.6) | – | 16 | 177.8 (105.2-274.6) | – |
| Oc. spp. | 0 | 0 | 0 | 0 | 0 | ||
Subgroup meta-analysis of field studies reporting pool prevalence Dirofilaria immitis infected/infective rates in vectors grouped by country_
| Minimum infected ratea | Minimum infective rateb | ||||||
|---|---|---|---|---|---|---|---|
| Variable | Pool size | Positive pool | Overall prevalence (95% CI) | I 2c | Positive pool | Overall prevalence (95% CI) | I 2 |
| Global | 124,480 | 1,071 | 21.9 (14-31.2) | 98.6 | 235 | 2.6 (1-4.8) | 94.4 |
| PAHO | 18,690 | 451 | 32.4 (13.3-59) | 98.2 | 101 | 3.8 (0.1-11.1) | 95.3 |
| Argentina | 2,462 | 5 | 0 (0-1.4) | 99.9 | 0 | 0 (0-0.3) | 99.8 |
| Brazil | 3,988 | 56 | 13.2 (9.8-17.1) | 99.9 | 8 | 1.4 (0.3-3) | 99.8 |
| Mexico | 867 | 32 | 25 (15.4-36.8) | 99.9 | 21 | 9.4 (3.7-17.3) | 99.8 |
| USA | 11,373 | 358 | 57.9 (8.1-146.5) | 99 | 72 | 4 (0-23.4) | 96.8 |
| EURO | 57,717 | 240 | 14.8 (5-28.7) | 97.2 | 71 | 2.2 (0.1-6.2) | 92.9 |
| Italy | 3,808 | 121 | 30.3 (3.1-80.6) | 97.7 | 30 | 6.3 (0-20.8) | 91.9 |
| Portugal | 2,389 | 58 | 23.1 (17.4-29.6) | 99.5 | 25 | 10 (6.3-14.5) | 98.4 |
| Slovakia | 187 | 4 | 14.7 (0.9-39.4) | 99.5 | 0 | 0 (0-10.2) | 98.4 |
| Spain | 2,825 | 4 | 1.3 (0.2-3.2) | 0 | 1 | 0.1 (0-1.3) | 0 |
| Turkey | 613 | 17 | 24.5 (12.7-39.3) | 5.1 | 15 | 21.4 (10.4-35.5) | 34.2 |
| Czech | 237 | 0 | 0 (0-15.4) | 0 | 0 | 0 (0-15.4) | 0 |
| France | 797 | 29 | 36.4 (24.5-51.8) | – | 0 | 0 (0-4.6) | – |
| Germany | 955 | 2 | 2.1 (0.3-7.5) | – | 0 | 0 (0-3.9) | – |
| Russia | 78 | 5 | 64.1 (21.2-143) | – | 0 | 0 (0-46.2) | – |
| Australia | 2,389 | 0 | 0 (0-0.1) | – | 0 | 0 (0-0.1) | – |
| EMRO | 190 | 15 | 78.9 (44.9-126.9) | – | 10 | 52.6 (25.5-94.7) | – |
| Iran | 190 | 15 | 78.9 (44.9-126.9) | – | 10 | 52.6 (25.5-94.7) | – |
| WPRO | 47,883 | 365 | 25.6 (6.1-57.4) | 98.9 | 53 | 0.3 (0-2.0) | 81.2 |
| French Polynesia | 1,194 | 28 | 23.5 (15.6-33.7) | – | 4 | 3.4 (0.9-8.6) | – |
| Samoa | 41,980 | 179 | 4.3 (3.7-4.9) | – | 49 | 1.2 (0.9-1.5) | – |
| Taiwan | 4,537 | 146 | 32.2 (27.2-37.7) | – | 0 | 0 (0.0-0.8) | – |
| South-Korea | 172 | 12 | 69.8 (36.6-118.7) | – | 0 | 0 (0.0-21.2) | – |
Subgroup meta-analysis of studies reporting Dirofilaria immitis infected and infective rates in vectors grouped by mosquito genus and species_
| Minimum infected ratea | Minimum infective rateb | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Variable | pool size | Positive pool | Overall prevalence (95% CI) | I 2c | Q | Positive pool | Overall prevalence (95% CI) | I 2 | Q |
| Total | 124,480 | 1,071 | 21.86 (14.06-31.1) | 98.5 | 2,475.9 | 235 | 2.6 (0.97-4.77) | 94.4 | 622.1 |
| Aedes | 62,924 | 526 | 29.5 (17.21-46.4) | 97.5 | 1,016.7 | 138 | 1.8 (0.03-5.3) | 91.6 | 298.4 |
| Culex | 16,652 | 260 | 12.36 (5.8-20.88) | 92.9 | 241.8 | 42 | 1.28 (0.0-4.04) | 83.3 | 95.6 |
| Anopheles | 4,244 | 157 | 51.37 (5-133.5) | 98.1 | 372.9 | 19 | 3.14 (0.0-12.2) | 75.5 | 28.6 |
| Ochlerotatus | 5,382 | 73 | 43.29 (0.1-140.6) | 96.3 | 54.9 | 24 | 0.97 (0.14-2.27) | 0.0 | – |
| Cx. quinciafasiatus | 4,892 | 168 | 24.7 (7.79-49.4) | 92 | 62.7 | 13 | 2.6 (0.0-12.46) | 87.6 | 40.2 |
| Ae. polynesiensis | 24,041 | 198 | 31.8 (3.5-85.5) | 98 | 100.8 | 53 | 1.8 (0.5-3.86) | 32.7 | 2.9 |
| Oc. taeniorhynchus | 2,517 | 44 | 12.6 (8.42-17.5) | 0.0 | – | 32 | 4.1 (1.73-7.31) | 0.0 | – |
| Oc. sollicitans | 2,539 | 25 | 0 | – | – | 2 | 0 | – | – |
| Cx. pipiens | 5,518 | 43 | 6.7 (3.48-10.88) | 59.7 | 19.8 | 7 | 0.62 (0-2.29) | 48.3 | 15.5 |
| Ae. ochcaspius | 285 | 14 | 48.6 (25.81-77.6) | 0.0 | – | 4 | 10.7 (0.91-27.7) | 0.0 | – |
| Ae. vexans | 13,439 | 77 | 47.1 (1.08-135) | 97.6 | 299.3 | 30 | 6.2 (0.0-38.53) | 94.0 | 117.2 |
| Cx. theileri | 1,574 | 43 | 35.3 (2.06-101.4) | 96.2 | 78.5 | 25 | 19.2 (0.06-62.5) | 94.5 | 54.3 |
| Ae. albopictus | 2,298 | 151 | 49.5 (14.7-101.6) | 95.3 | 169.7 | 25 | 3.2 (0.00-15.30) | 86.3 | 58.6 |
Characteristics of the individual studies included in the meta-analysis based on eligibility criteria_
| Country | Year of implementation | Method | Total sample | Total pool | Total infected pool | Total infective pool | Quality score | References |
|---|---|---|---|---|---|---|---|---|
| Brazil | 2013 | PCR | 3115 | 311 | 1 | 0 | 7 | Ogawa et al. (2013) |
| Mexico | 2015 | PCR | 2618 | 595 | 4 | 0 | 6 | Oswaldo et al. (2018) |
| USA | 2006 | PCR | 1,922 | 390 | 33 | 0 | 7 | Chambers et al. (2009) |
| Mexico | 2007 | Dissection | 272 | 272 | 28 | 21 | 8 | Manrique-Saide et al. (2008) |
| Italy | 2012 | PCR | 40,892 | 955 | 21 | 0 | 7 | Latrofa et al. (2012) |
| Iran | 2005-2011 | PCR | 190 | 190 | 15 | 10 | 6 | Azari-Hamidian et al. (2009) |
| USA | 2009 | PCR | 91,798 | 1,212 | 184 | 54 | 8 | Mckay et al. (2013) |
| Germany | 2011-2013 | PCR | 16,878 | 955 | 2 | 0 | 7 | Kronefeld et al. (2014) |
| Italy | 2000-2002 | PCR | 3,198 | 1,364 | 10 | 4 | 6 | Cancrini et al. (2006) |
| Brazil | 1995-1996 | Dissection | 3,677 | 3,677 | 55 | 8 | 7 | Labarthe et al. (1998) |
| Portugal | 2011-2013 | PCR | 5,866 | 1,815 | 54 | 23 | 8 | Ferreira et al. (2015) |
| Argentina | 2003-2005 | Dissection | 2,380 | 2,380 | 3 | 0 | 7 | Vezzani et al. (2006) |
| Russia | 2007-2017 | PCR | 387 | 78 | 5 | 0 | 8 | Shaikevich et al. (2018) |
| USA | 1994 | Dissection | 188 | 188 | 3 | 0 | 6 | Comiskey and Wesson (1995) |
| Italy | 2002-2003 | PCR | 1,576 | 880 | 6 | 3 | 5 | Cancrini et al. (2007) |
| Italy | 2003 | PCR | 154 | 154 | 2 | 1 | 6 | Cancrini et al. (2003a, 2003b) |
| Italy | 2000-2002 | Dissection | 2,534 | 336 | 81 | 22 | 5 | Cancrini et al. (2003a, 2003b) |
| Spain | 2005-2007 | PCR | 1,219 | 1,219 | 1 | 0 | 7 | Morchón et al. (2011) |
| Argentina | 2007-2008 | PCR | 453 | 82 | 2 | 0 | 6 | Vezzani et al. (2011) |
| Portugal | 2002-2003 | PCR | 554 | 554 | 4 | 2 | 7 | Santa-Ana et al. (2006) |
| Turkey | 2008-2009 | PCR | 6,153 | 559 | 15 | 14 | 8 | Yildirim et al. (2011) |
| Spain | 2012-2013 | PCR | 881 | 881 | 1 | 1 | 6 | Bravo-Barriga et al. (2016) |
| Turkey | 2008 | PCR | 301 | 54 | 2 | 1 | 8 | Bıs¸kın et al. (2010) |
| Slovakia | 2013 | PCR | 10,500 | 105 | 4 | 0 | 8 | Bocková et al. (2015) |
| Spain | 2004-2006 | PCR | 725 | 725 | 2 | 0 | 7 | Morchon et al. (2007) |
| USA | 1985-1987 | Dissection | 9,377 | 9,377 | 123 | 18 | 7 | Parker (1993) |
| South-Korea | 2005 | PCR | 2,059 | 172 | 12 | 0 | 6 | Lee et al. (2007) |
| USA | 2006-2007 | PCR | 1,401 | 206 | 15 | 0 | 8 | Licitra et al. (2010) |
| France | 2015 | Real time PCR | 797 | 797 | 29 | 0 | 8 | Tahir et al. (2017) |
| Italy | 2005 | PCR | 637 | 119 | 1 | 0 | 7 | Masetti et al. (2008) |
| Taiwan | 1997 | Dissection | 4,537 | 4,537 | 146 | 0 | 6 | Lai et al. (2001) |
| Samoa | 1978-1980 | Dissection | 41,980 | 41,980 | 179 | 49 | 7 | Samarawickrema et al. (1992) |
| French Polynesia | 2003-2004 | Dissection | 1,194 | 1,194 | 28 | 4 | 8 | Russell et al. (2005) |
List of published articles included in the systematic review for experiment studies of D_ immitis in vectors_
| Country | Year of implementation | Detection method | Total sample | Total pool | Total infected pool | Total infective pool | Quality score | References |
|---|---|---|---|---|---|---|---|---|
| Brazil | 2000 | Dissection | 756 | 756 | 225 | 57 | 8 | Ahid et al. (2000) |
| Italy | 2017 | PCR | 136 | 136 | 66 | 10 | 7 | Silaghi et al. (2017) |
| Italy | 2015 | PCR | 45 | 45 | 37 | 18 | 8 | Montarsi et al. (2015) |
| Iran | 2017 | PCR | 90 | 90 | 58 | 16 | 7 | Solgi et al. (2017) |
| Brazil | 2008 | Dissection | 1,942 | 1,942 | 465 | 0 | 8 | Carvalho et al. (2008) |
| USA | 2005 | Dissection | 750 | 750 | 630 | 0 | 8 | Debboun et al. (2005) |
| Brazil | 1998 | Dissection | 73 | 73 | 43 | 0 | 7 | Macêdo et al. (1998) |
| Australia | 1989 | Dissection | 215 | 215 | 0 | 49 | 6 | Russell et al. (2005) |
| Brazil | 1999 | Dissection | 505 | 505 | 0 | 101 | 8 | Brito et al. (1999) |
Subgroup meta-analysis of field studies reporting pool prevalence D_ immitis infected and infective rates in vectors grouped by risk factor_
| Minimum infected ratea | Minimum infective rateb | ||||||
|---|---|---|---|---|---|---|---|
| Variable | Pool size | Positive pool | Overall prevalence (95% CI) | I 2c | Positive pool | Overall prevalence (95% CI) | I 2 |
| Latitude | |||||||
| 0-20 | 44,470 | 245 | 16.9 (3.2-40.1) | 96.6 | 53 | 0.5 (0.2-0.9) | 1.8 |
| 20-40 | 25,560 | 609 | 29 (15.1-46.9) | 97.7 | 129 | 5.7 (1.3-12.2) | 95.1 |
| >40 | 54,450 | 217 | 17.4 (4.5-37) | 98.3 | 53 | 1.70 (0-6.1) | 93.1 |
| Longitude | |||||||
| 0-10 | 4,218 | 86 | 13.1 (1.3-36) | 95.7 | 24 | 1.9 (0-9.5) | 90.9 |
| 10-20 | 52,621 | 128 | 12 (1.8-29.6) | 98.1 | 32 | 2.1 (0-6.7) | 93.3 |
| 20-50 | 4,745 | 96 | 29.9 (12.9-52.6) | 81.9 | 33 | 8.4 (0-26-9) | 87.8 |
| 50-80 | 12,150 | 129 | 6.1 (0-18.8) | 93.7 | 18 | 0 (0-1.4) | 66.9 |
| 80-110 | 2,473 | 234 | 58.1 (9.1-143) | 97.7 | 75 | 12.5 (0-49) | 96 |
| >110 | 48,273 | 398 | 34.8 (11.5-69.4) | 98.8 | 53 | 0.3 (0-1.7) | 75.1 |
| Mean temperature °C | |||||||
| 7-14.9 | 52,431 | 190 | 23.3 (7.3-46.9) | 98 | 47 | 2.5 (0-8.1) | 92.3 |
| 15-21.9 | 18,905 | 404 | 19.6 (6-39.9) | 98.1 | 106 | 4.1 (0.4-10.4) | 94.2 |
| 22-28.1 | 53,144 | 477 | 23.9 (10.8-41.5) | 98.1 | 82 | 1.9 (0.1-5.1) | 90.9 |
| Annual rainfall (mm) | |||||||
| <250 | 49,029 | 5 | 0.4 (0-3) | 79.5 | 1 | 0 (0-0.1) | 37.3 |
| 251-500 | 24,280 | 509 | 27.8 (16.6-41.5) | 96 | 100 | 5.1 (1.4-10.2) | 92 |
| 501-1,000 | 8,801 | 345 | 32 (9.8-65.7) | 97.9 | 85 | 3.4 (0-12.7) | 94.9 |
| >1,000 | 42,370 | 212 | 3.9 (3.3-4.6) | 99.7 | 49 | 0.6 (0.3-0.9) | 99.3 |
| Sea level (m) | |||||||
| <25 | 15,367 | 281 | 28.7 (12.4-50.9) | 96.4 | 52 | 3.4 (0.2-9.1) | 87.8 |
| 26-100 | 6,945 | 291 | 36.1 (4.7-93.7) | 98.9 | 98 | 11.2 (0.3-34.6) | 97.6 |
| 101-200 | 95,282 | 379 | 13.3 (4.1-26.8) | 99.2 | 57.9 | 0 (0-1.1) | 93.7 |
| 201-1000 | 4,067 | 58 | 12.3 (1.4-31.7) | 94 | 3 | 0.1 (0-1) | 0 |
| >1,000 | 2,819 | 62 | 27.8 (4.4-67.3) | 95.1 | 25 | 10 (0-35.1) | 93.8 |
| Mean humidity (%) | |||||||
| <65 | 5,171 | 73 | 12.3 (1.5-29.6) | 89.5 | 24 | 5.8 (0-19.6) | 89.6 |
| 66-70 | 15,821 | 413 | 26.9 (6.1-61.1) | 98.8 | 104 | 7.4 (1.2-18) | 95.9 |
| 71-75 | 51,514 | 132 | 24.4 (8.2-48.1) | 97.6 | 31 | 1.8 (0-7.1) | 91 |
| 76-80 | 8,579 | 235 | 22.2 (9.9-38.8) | 93.1 | 27 | 1.2 (0-8.5) | 93.7 |
| >80 | 43,395 | 218 | 14.1 (0.9-39.4) | 95.3 | 0.49 | 0.1 (0-0.3) | 0 |
| Detection method | |||||||
| PCR | 60,539 | 425 | 19.3 (7.9-34.9) | 98.3 | 113 | 2 (0-5.7) | 93.7 |
| Dissection | 63,941 | 646 | 30.5 (1.5-48.5) | 98.8 | 122 | 4.5 (1.6-8.6) | 95.2 |
| Implementation year | |||||||
| 1992-2000 | 55,222 | 360 | 10.5 (4-19.7) | 97.3 | 75 | 0.9 (0.4-1.6) | 40.7 |
| 2000-2005 | 6,221 | 257 | 57.3 (14.5-124.7) | 98 | 27 | 9.6 (0-36.4) | 96.6 |
| 2006-2010 | 8,525 | 132 | 24.4 (10.1-43.9) | 95.3 | 41 | 3.7 (0.1-10.3) | 89.6 |
| 2011-2015 | 6,313 | 283 | 19.9 (2.6-50.2) | 94.4 | 91 | 3.8 (0-14.6) | 93.5 |
| 2016-2018 | 48,199 | 39 | 10.3 (0–35.1) | 97.4 | 1 | 0 (0-0.1) | 45.4 |