HIV infection with late diagnosis

The main facts and figures show that:

  • overall, in the period from 2015 to 2017, an average of 41.1% of people aged 15 years and older who were newly diagnosed with HIV in England were diagnosed at a late stage of infection
  • in the same period, the percentage of people whose HIV diagnosis was made at a late stage of infection was significantly higher than the England average among the Black African, Other Black, Black Caribbean, and Asian ethnic groups
  • in the same period, the percentage of people whose HIV diagnosis was made at a late stage of infection was significantly lower than the England average among the White, and Other (including Mixed ethnicity) groups
  • between 2009/11 and 2015/17, the percentage of people whose HIV diagnosis was made at a late stage of infection significantly declined for the Black African, Other (including Mixed ethnicity), and White ethnic groups; although the figures show a large drop for the Other Black group, there were too few people in this group to draw firm conclusions
Things you need to know

The data for HIV diagnoses made at a late stage are shown as averages over a series of overlapping 3-year periods. This has been done due to a small number of diagnoses in individual years. By averaging over a 3-year period, the numbers of patients are large enough to break down the data by ethnicity without the need for suppression.

Newly diagnosed patients were excluded from the figures if either:

  • the count of their CD4 cells (a type of white blood cell) was not recorded within 91 days – this occurred in around 15% of cases
  • their place of residence was not recorded

The data submitted by some service providers may therefore not be representative of all newly diagnosed patients.

For the period from 2015 to 2017, ethnicity was known for 94% of people newly diagnosed with HIV.

What the data measures

This data measures the percentage of HIV diagnoses among residents of England aged 15 years or older that are made at a late stage of infection.

Late stage infection is identified by laboratory tests on the patient’s blood, which analyse the count of CD4 cells (a type of white blood cell) at the time of diagnosis. The diagnosis is classed as ‘late stage’ if the patient has a CD4 count of fewer than 350 cells per cubic millimetre (mm3) of blood.

The data only includes patients with CD4 cell counts that are available within 91 days of diagnosis. Counts available after this period are not counted as having been taken at the time of diagnosis, and may be affected if the patient has started treatment.

CD4 is a type of white blood cell that’s necessary for a healthy immune system. If untreated, an HIV infection will diminish the number of CD4 cells over time. Clinical guidelines recommend that patients should begin anti-retroviral therapy when CD4 cells counts drop to fewer than 350 cells per mm3.

The ethnic categories used in this data

Data is broken down into the following 6 groups due to the small numbers of patients with a new HIV diagnosis in some ethnic groups and the need to protect patient confidentiality:

  • Asian
  • Black African
  • Black Caribbean
  • Any other Black
  • White
  • Other ethnic groups (including Mixed ethnicities)

Ethnic groups and how data on ethnicity is collected

HIV infection with late diagnosis by ethnicity

Number and percentage of people aged 15 years and older newly diagnosed with HIV who were diagnosed at a late stage of infection, by ethnicity over time

2015 - 17 2014 - 16 2013 - 15 2012 - 14 2011 - 13 2010 - 12 2009 - 11
Ethnicity New diagnoses % late-stage New diagnoses % late-stage New diagnoses % late-stage New diagnoses % late-stage New diagnoses % late-stage New diagnoses % late-stage New diagnoses % late-stage
All 10,848 41.1 12,636 40.4 13,568 40.5 14,045 43.2 14,312 45.8 14,663 48.5 15,016 50.2
Asian 640 47.8 750 47.6 805 45.1 830 48.1 790 48.7 740 53.0 665 51.4
Black
Black African 1,945 55.2 2,430 55.6 2,770 56.5 3,200 59.3 3,680 61.4 4,245 62.8 4,760 64.0
Black Caribbean 270 48.5 325 45.4 410 44.6 430 45.6 445 48.8 455 51.8 515 49.3
Black other 195 51.3 235 46.6 255 46.7 290 50.2 300 52.7 305 55.6 315 57.0
White 6,255 36.9 7,365 35.3 7,930 34.7 8,095 36.5 8,025 38.7 7,890 40.6 7,790 42.0
Other inc Mixed 900 36.2 1,000 35.6 985 37.0 935 38.7 870 40.2 885 42.2 855 44.5

Download table data (CSV) Source data (CSV)

Summary

This data shows that:

  • overall, in the period from 2015 to 2017, an average of 41.1% of people aged 15 years and older who were newly diagnosed with HIV were diagnosed at late stage of infection (4,461 out of 10,848 people)
  • in the same period, the percentage of people whose HIV diagnosis was made at a late stage of infection was significantly higher than the England average among the Black African, Other Black, Black Caribbean and Asian ethnic groups (at 55.2%, 51.3%, 48.5% and 47.8% respectively), and significantly lower than the England average among the White and Other (including Mixed ethnicity) groups (at 36.9% and 36.2% respectively)
  • between 2009/11 and 2015/17, the percentage of people whose HIV diagnosis was made at a late stage of infection fell significantly for Black African people (from 64.0% to 55.2%), people from the Other (including Mixed ethnicity) group (from 44.5% to 36.2%), and White people (from 42.0% to 36.9%)
  • although there appears to be a large drop for the Other Black group in the same period, there were too few people in this group to draw firm conclusions
  • throughout the period from 2009/11 to 2015/17, the percentage of people whose HIV diagnosis was made at a late stage of infection was significantly higher in the Black African ethnic group compared with all other ethnic groups (except for the Black Caribbean Group in 2015/17 and Other Black ethnic group in the periods 2009/11, 2010/12, and 2015/17)

Methodology

Methodology

Data on patients newly diagnosed with HIV and those accessing HIV care is collected and processed using the HIV and AIDS Reporting System (HARS) dataset. The dataset includes laboratory reports of patients’ CD4 blood counts.

HARS data is submitted every 3 months by all outpatient HIV service providers.

The data on diagnoses of HIV at a late stage is collected, validated, de-duplicated and matched using HARS by the HIV & STI department of PHE’s National Infections Service.

Data is as reported by service providers but relies on ‘record linkage’ to integrate data and ‘de-duplication’ to prevent double counting of the same individual. Every effort is made to ensure accuracy and completeness of the data, including web-based reporting with integrated checks on data quality. However, responsibility for the accuracy and completeness of data lies with the service providers that submit the data. Service providers have to follow a data sharing policy to ensure data is consistent and patient confidentiality is protected.

Data supplied for previous years is updated every year to account for clinic/laboratory resubmissions and improvements to data cleaning.

Confidence intervals:

The confidence intervals for the estimate of the percentage of all newly diagnosed adults with late HIV diagnosis are available if you download the data.

In the period from 2015-17, the percentage of late HIV diagnoses for people of White ethnicity aged 15 years and over was 36.9%. This is a reliable estimate based on the number of people diagnosed with late stage HIV infection as a proportion of those who were newly diagnosed, but it is not possible to be 100% certain of the true rate of late diagnosis for this population due to the effect of natural variation.

It’s 95% certain, however, that the rate of diagnosis of HIV at a late stage of infection lies somewhere between 35.7% and 38.2% of White people who were newly diagnosed with HIV. In statistical terms, this is a 95% confidence interval. This means that 95 times out of 100 the estimate would fall in this range (i.e. between the upper and lower confidence interval). But 5 times out of 100 it would fall outside this range.

The smaller the number of new diagnoses, the more uncertain the estimate and the wider the confidence interval. To illustrate this, in the period from 2015-17 there were fewer diagnoses of HIV infection among people from the Black Other ethnic group than for White people, so we can be less certain about the estimate of 51.3% diagnosed with HIV infection at a late stage for the Other Black ethnic group. This greater uncertainty is expressed by the wider confidence interval of between 44.0% to 58.5% of people from the Other Black ethnic group, who were newly diagnosed at a late stage of HIV infection.

Statistically significant differences are where the 95% confidence interval around the estimate for an ethnic group does not overlap with the confidence interval around the estimate for the group it’s being compared with.

Rounding

Percentages are rounded to 1 decimal point. Download the data for unrounded figures.

Related publications

HIV annual data tables and report present national data. Local level data is available for related indicators in the Sexual and Reproductive Health Profiles tool but the local data cannot be broken down by ethnicity.

Further technical information

To reflect the 2008 British HIV Association (BHIVA) treatment guidelines, the definition of a late HIV diagnosis was updated from a CD4 count of less than 200 cells/mm3 within 91 days of diagnosis to less than 350 cells/mm3 within 91 days of diagnosis. The data for all of the years presented here reflects the updated definition of a late-stage infection (of fewer than 350 cells/mm3). The method for calculating confidence intervals at 95% significance was based on the exact binomial (Clopper-Pearson) interval. This method produces a slightly wider confidence interval, and is thus slightly more conservative in determining significant difference, compared to the Wilson score interval. Further information on HIV surveillance can be found on GOV.UK in the HIV: surveillance, data and management collection.

Data sources

Source

Type of data

Administrative data

Type of statistic

Official statistics

Publisher

Public Health England

Publication frequency

Yearly

Purpose of data source

The HIV and AIDS Reporting System (HARS) dataset is designed to increase the efficiency of HIV surveillance, enhance standard outputs on HIV surveillance, produce quality of care indicators, and directly support commissioning services.

People who have a late-stage HIV infection have usually had HIV for at least 3 years, and are therefore at a higher risk of premature death and of transmitting the virus to their sexual partners. For this reason, reducing late HIV diagnosis is a clinical and public health priority.

The HARS dataset was developed by Public Health England (PHE) in conjunction with Department of Health and the Clinical Reference Group for HIV.

Download the data

HIV infection with late-stage diagnosis - Spreadsheet (csv) 7 KB

This file contains the following: ethnicity, 3 year aggregated time period, value, numerator, denominator, confidence intervals