An Assessment of Trends in HIV-1 Prevalence and Incidence and Spatio-Temporal Analyses of HIV-1 Recent Infection Among MSM During the Surveillance Period Between 2018 and 2022 in Sichuan, China

Figures & data

Figure 1 Distribution of MSM sentinel surveillance sites (n=10) in Sichuan, 2018–2022.Map created by ArcGIS 10.7 software (ESRI Inc., Redlands.CA.USA).

Table 1 HIV-1 Prevalence and Incidence Year by Year from 10 MSM Sentinel Surveillance Sites

Region	Year	The Number of Cases^a	The Number of HIV Antibody-Negative Cases^b	The Number of HIV Antibody-Positive Cases^c	The Number of Previously Reported Cases^d	The Number of Newly Diagnosed Cases^e	The Number of Samples Tested with LAg-Avidity Assay^f	The number of Recently Infected Cases^g	Prevalence Rate(%)		Estimated Incidence Rate(%, 95% CI)
10 sites	2022	3505	3330	173	120	53	53	31	1.51	χ2=24.031, p < 0.001	2.37	χ2=29.225, p < 0.001
											(1.54, 3.21)
	2021	3265	3074	188	111	77	76	40	2.36		3.4
											(2.34, 4.45)
	2020	3208	2986	219	113	106	106	60	6.83		4.42
											(3.30, 5.53)
	2019	3286	3063	223	124	99	95	40	6.79		2.57
											(1.77, 3.36)
	2018	3433	3160	262	140	122	119	59	7.63		3.96
											(2.95, 4.98)
	2018–2022	16,697	15,613	1065	608	457	449	230	2.74		3.69
											(3.21, 4.16)

Notes: ^aThe number of cases means individuals participated in HIV-1 MSM sentinel surveillance program. ^bHIV antibody-negative cases means those got negative result in twice enzyme immunoassay screening. ^cHIV antibody-positive cases means those got positive result in twice enzyme immunoassay screening. ^dPreviously reported cases means those previously reported positive in confirmatory tests and was reported in the China HIV/AIDS case reporting system. ^eNewly diagnosed cases means those got positive result in confirmatory tests and was not yet reported in the China HIV/AIDS case reporting system. ^fSamples tested with LAg-Avidity assay means those were test by the LAg-Avidity assay. ^gRecently infected cases means those were classified as LAg-Avidity positive.

Figure 2 The trends of HIV-1 prevalence and incidence during the surveillance period between 2018 and 2022 among men who have sex with men in Sichuan, China.

Table 2 HIV-1 Prevalence and Incidence from Different MSM Sentinel Surveillance Sites

Region	Year	The Number of cases ^a	The Number of HIV Antibody-Negative Cases ^b	The Number of HIV Antibody-Positive Cases ^c	The Number of Previously Reported Cases ^d	The Number of Newly Diagnosed Cases ^e	The Number of Samples Tested with LAg-Avidity Assay ^f	The Number of Recently Infected Cases ^g	Prevalence Rate(%)	Estimated Incidence Rate(%, 95% CI)	Region	Year
Chengdu	2018–2022	2019	1920	98	12	86	83	35	4.26	χ2=95.934, P<0.0001	4.6 (3.07, 6.12)	χ2=129.588, P< 0.0001
Dazhou	2018–2022	2000	1863	137	104	33	32	10	1.65		1.24 (0.47, 2.01)
Deyang	2018–2022	1996	1876	113	57	56	56	24	2.81		3.09 (1.85, 4.32)
Guangyuan	2018–2022	1260	1122	138	124	14	14	6	1.11		1.23 (0.24, 2.21)
Leshan	2018–2022	879	868	11	10	1	0	0	0.11		0
Liangshan	2018–2022	1283	1233	49	15	34	32	10	2.65		2 (0.76, 3.23)
Luzhou	2018–2022	1999	1849	147	62	85	84	80	4.25		10.74 (8.39, 13.10)
Mianyang	2018–2022	2051	1959	92	13	79	79	31	3.85		3.83 (2.48, 5.17)
Yibin	2018–2022	2000	1910	90	39	51	51	25	2.55		3.27 (1.99, 4.56)
Zigong	2018–2022	1210	1013	190	172	18	18	9	1.49		1.96 (0.68, 3.24)

Notes: ^aThe number of cases means individuals participated in HIV-1 MSM sentinel surveillance program. ^bHIV antibody-negative cases means those got negative result in twice enzyme immunoassay screening. ^cHIV antibody-positive cases means those got positive result in twice enzyme immunoassay screening. ^dPreviously reported cases means those previously reported positive in confirmatory tests and was reported in the China HIV/AIDS case reporting system. ^eNewly diagnosed cases means those got positive result in confirmatory tests and was not yet reported in the China HIV/AIDS case reporting system. ^fSamples tested with LAg-Avidity assay means those were test by the LAg-Avidity assay. ^gRecently infected cases means those were classified as LAg-Avidity positive.

Figure 3 Hot-spots of HIV-1 recent cases at city level by year among MSM between 2018 and 2022. (A) Sichuan province, 2018. (B) Sichuan province, 2019. (C) Sichuan province, 2020. (D) Sichuan province, 2021. (E) Sichuan province, 2022.