Nepal: Dengue Outbreak - Jun 2023

In Nepal, dengue cases usually increase in July, coinciding with monsoon season, falling between June and September, with most cases reported in September. Hence, the approximate impact will be from July to September 2023, with 3,500 to 4,000 cases reported, as projected by the Ministry of Health and Population (MoHP). This year, as per epidemiological data collected up to April 2023, 600 cases have already been diagnosed which is highly alarming considering the usual incidence pattern in Nepal. (IFRC, 14 June 2023)

As of 15 July, 2023 a total of 2,930 dengue cases have been identified from 68 districts, with Koshi province reporting highest number (1746), followed by Bagmati province (468) and Sudurpaschim Province (279). [...] The Epidemiology and Disease Control Division (EDCD) has been conducting routine surveillance of dengue cases through the Early Warning and Reporting System (EWARS). The line-lists of Dengue cases have been shared with 92 local levels in 66 districts to initiate timely response. (Govt. of Nepal, 15 Jul 2023)

As of 24 July, 2023 a total of 4289 dengue cases have been identified from 69 districts, with Koshi province reporting highest number (2754), followed by Bagmati province (667), Gandaki Province (344) and Sudurpaschim Province (316) [...] The top 10 districts account for 85 % of all reported cases (3671 cases), while the cases are sporadic in other districts. These top 10 districts include Sunsari (2542), Dhading (401), Kaski (205), Darchula (190), Kathamandu (80) Sankhuwasabha (64), Myagdi (54) Kanchanpur (52), Rupandehi (45), Morang (38). Mortality of 3 dengue cases has been verified and 1 associated with severe dengue shock syndrome and 2 from the dengue and other comorbidities. (Govt. of Nepal, 24 Jul 2023)

As of 30 July, 2023 a total of 5688 dengue cases have been identified from 70 districts, with Koshi province reporting highest number (3821), followed by Bagmati province (962), Gandaki Province (357) and Sudurpaschim Province (325). [...] The top 10 districts account for 87 % of all reported cases (4939 cases), while the cases are sporadic in other districts. [...] These top 10 districts include Sunsari (3486), Dhading (655), Kaski (208) Darchula (191), Kathamandu (96) Sankhuwasabha (75), Myagdi (58), Morang (57) Kanchanpur (57) and Jhapa (56) [...]. Mortality of 4 dengue cases has been verified and 1 associated with server dengue shock syndrome and 3 from the dengue and other comorbidities. (Govt. of Nepal, 31 Jul 2023)

As of 7th August, 2023 a total of 9411 dengue cases have been identified from 74 districts, with Koshi province reporting the highest number (6934), followed by Bagmati province (1391), Gandaki Province (419) and Sudurpaschim Province (380). The mortality of eight dengue cases has been verified, with one case associated with severe dengue shock syndrome, and the remaining seven cases resulting from dengue along with other comorbidities. (Govt. of Nepal, 7 Aug 2023)

As of 9th August, 2023 a total of 11,157 dengue cases have been identified from 74 districts, with Koshi province reporting highest number (8420), followed by Bagmati province (1547), Gandaki Province (481) and Sudurpaschim Province (404). The top 10 districts account for 89.6% of all reported cases (10,007 cases), while the cases are sporadic in other districts; the top 10 districts include Sunsari (6300), Morang (1393), Dhading (1110), Kaski (227), Dhankuta (223) Darchula (192), Jhapa (182), Kathmandu (153), Sankhuwasabha (148) and Tanahu (79). (Govt. of Nepal, 9 Aug 2023)

The number of dengue infected people in Kathmandu Valley has exceeded 800. According to the Epidemiology and Disease Control Division (EDCD), among the three districts of the valley, 463 people have been infected with dengue in Kathmandu, 172 in Bhaktapur and 185 in Lalitpur. Government data has shown that the infection rate has increased in the valley in the last one month. Anup Bastola, Head of the Therapeutic Division of the Department of Health Services, said that there is a fear that dengue infection will spread throughout the country including the valley by November. This year, 14 people have died due to dengue infection so far and 12 of the deaths are from outside the valley. (WHO, 11 Sep 2023)

Between 1 January and 27 September 2023, 32,897 cases of dengue including 20 confirmed deaths (CFR=0.06%) have been reported from 76 districts in Nepal. The highest cumulative number of cases and case incidence have been reported from Sunsari district, Koshi province (16,036 cases (48.7% of the total), 1,804.4 cases per 100 000). The second highest number of cumulative cases has been reported from Jhapa district, Koshi province (3,538 cases (10.7% of the total), 389.6 cases per 100 000) and the second highest incidence of cases from Dhading district, Bagmati province (3,050 cases (9.3% of the total), 867.4 per 100,000 population). A total of 1,365 cases of dengue were reported in Nepal during week 38 (17 to 23 September 2023) via the Early Warning Reporting System (EWARS), a 3.7% decrease compared to week 37 (10 to 16 September, n= 1,418). (WHO, 4 Oct 2023)

Between 1 January and 13 October 2023, 39,360 cases of dengue including 20 confirmed deaths (CFR=0.05%) have been reported from 76 districts in Nepal. The highest cumulative number of cases and case incidence have been reported from Sunsari district, Koshi province (16,096 cases (40.9% of the total), 1,811.1 cases per 100,000). The second highest number of cumulative cases and case incidence have been reported from Tanahun district, Gandaki province (5,050 cases (12.8% of the total), 1,472 cases per 100,000). A total of 1,755 cases of dengue were reported in Nepal during week 40 (1 to 7 October 2023) via the Early Warning Reporting System (EWARS), an 8.4% increase compared to week 39 (24 to 30 September, n= 1 619). (WHO, 18 Oct 2023)

A total of 267,680 dengue cases (defined as dengue NS1 or anti-dengue virus IgM positive) including 1,333 deaths have been cumulatively reported between 1 January and 29 October 2023 with a case fatality rate (CFR) of 0.50%. During September 2023, a total of 79,598 cases including 396 deaths were reported. This was the highest number of monthly cases and deaths, compared with the available historical data from 2019 to 2023. Between 1 and 29 October at total of 64,274 cases including 344 deaths were reported. A total of 12,634 cases of dengue were reported in Bangladesh during week 43 (23 to 29 October 2023), an 18.1% decrease compared to the number of cases reported during week 42 (16 to 22 October 2023) (n=15 432). The number of new deaths also decreased to 78 in week 43 from 86 in week 42, a decrease by 9.3%. (WHO, 1 Nov 2023)

A total of 888 cases of dengue were reported in Nepal during week 44 (29 October to 4 November 2023) via the Early Warning and Reporting System (EWARS), an 8.7% decrease compared to week 43 (22 to 28 October, n= 973) (Figure 5). Between 1 January and 17 November 2023, 49,761 dengue cases, including 20 confirmed deaths (CFR=0.04%), have been reported from 77 districts in Nepal. The highest number of monthly cases in 2023 has been reported in September (n=13 472). The highest cumulative number of cases reported from Sunsari district, Koshi province (16,165 cases, 1,819 cases per 100,000 population), while the highest cumulative case incidence has been reported from Tanahu district, Gandaki province (6,924 cases, 2,019 cases per 100,000 population). Over time, the spatial distribution of cases has changed: In August 2023, incidence was highest in districts in Koshi province (Sunsari, Sankhuwasabha and Morang) as well as Dhading in Bagmati province; in October 2023, incidence was highest in districts in Gandaki province (Tanahun, Gorkha and Kaski). (WHO, 29 Nov 2023)