Update runtime files.
diff --git a/runtime/syntax/markdown.vim b/runtime/syntax/markdown.vim
index 0321ca3..17b61c2 100644
--- a/runtime/syntax/markdown.vim
+++ b/runtime/syntax/markdown.vim
@@ -2,7 +2,7 @@
 " Language:     Markdown
 " Maintainer:   Tim Pope <vimNOSPAM@tpope.org>
 " Filenames:    *.markdown
-" Last Change:  2019 Dec 05
+" Last Change:  2020 Jan 14
 
 if exists("b:current_syntax")
   finish
@@ -88,11 +88,11 @@
 if has('conceal') && get(g:, 'markdown_syntax_conceal', 1) == 1
   let s:concealends = ' concealends'
 endif
-exe 'syn region markdownItalic matchgroup=markdownItalicDelimiter start="\S\@<=\*\|\*\S\@=" end="\S\@<=\*\|\*\S\@=" skip="\\*" contains=markdownLineStart,@Spell' . s:concealends
+exe 'syn region markdownItalic matchgroup=markdownItalicDelimiter start="\S\@<=\*\|\*\S\@=" end="\S\@<=\*\|\*\S\@=" skip="\\\*" contains=markdownLineStart,@Spell' . s:concealends
 exe 'syn region markdownItalic matchgroup=markdownItalicDelimiter start="\w\@<!_\S\@=" end="\S\@<=_\w\@!" skip="\\_" contains=markdownLineStart,@Spell' . s:concealends
-exe 'syn region markdownBold matchgroup=markdownBoldDelimiter start="\S\@<=\*\*\|\*\*\S\@=" end="\S\@<=\*\*\|\*\*\S\@=" skip="\\*" contains=markdownLineStart,markdownItalic,@Spell' . s:concealends
+exe 'syn region markdownBold matchgroup=markdownBoldDelimiter start="\S\@<=\*\*\|\*\*\S\@=" end="\S\@<=\*\*\|\*\*\S\@=" skip="\\\*" contains=markdownLineStart,markdownItalic,@Spell' . s:concealends
 exe 'syn region markdownBold matchgroup=markdownBoldDelimiter start="\w\@<!__\S\@=" end="\S\@<=__\w\@!" skip="\\_" contains=markdownLineStart,markdownItalic,@Spell' . s:concealends
-exe 'syn region markdownBoldItalic matchgroup=markdownBoldItalicDelimiter start="\S\@<=\*\*\*\|\*\*\*\S\@=" end="\S\@<=\*\*\*\|\*\*\*\S\@=" skip="\\*" contains=markdownLineStart,@Spell' . s:concealends
+exe 'syn region markdownBoldItalic matchgroup=markdownBoldItalicDelimiter start="\S\@<=\*\*\*\|\*\*\*\S\@=" end="\S\@<=\*\*\*\|\*\*\*\S\@=" skip="\\\*" contains=markdownLineStart,@Spell' . s:concealends
 exe 'syn region markdownBoldItalic matchgroup=markdownBoldItalicDelimiter start="\w\@<!___\S\@=" end="\S\@<=___\w\@!" skip="\\_" contains=markdownLineStart,@Spell' . s:concealends
 
 syn region markdownCode matchgroup=markdownCodeDelimiter start="`" end="`" keepend contains=markdownLineStart